Edit the file Data\Equipment\market_misc.ini
Look for Hi01_01_base which is planet Malta
add a line MarketGood = shield03_mark10_lf, 30, -1, 10, 10, 0, 1
for the shield that you want.
The first number is the level you need to be at to buy the item, so you can change it from 30 to 0 to buy it at any level.
You will find all the info you need for editing in Compilation of ALL IDS names, Mod Info, Tutorials, INI explination all the equipment along with tons of other tasty information are listed here.
I don't want to spoil all the fun for you but if you still cant figure it out let us know.

[BaseGood
base = Hi01_01_base
MarketGood = fc_ou_gun01_mark01, 6, -1, 10, 10, 0, 1
MarketGood = fc_ou_gun01_mark02, 10, 0, 10, 10, 0, 1
MarketGood = fc_ou_gun01_mark03, 16, 0.200000, 10, 10, 0, 1
MarketGood = fc_ou_gun01_mark04, 26, 0.500000, 10, 10, 0, 1
MarketGood = fc_ou_gun01_mark05, 30, 0.750000, 10, 10, 0, 1
MarketGood = fc_ou_gun02_mark01, 6, -1, 10, 10, 0, 1
MarketGood = fc_ou_gun02_mark02, 10, 0, 10, 10, 0, 1
MarketGood = fc_ou_gun02_mark03, 16, 0.200000, 10, 10, 0, 1
MarketGood = fc_ou_gun02_mark04, 26, 0.500000, 10, 10, 0, 1
MarketGood = fc_ou_turret01_mark01, 6, -1, 10, 10, 0, 1
MarketGood = fc_ou_turret01_mark02, 16, 0, 10, 10, 0, 1
MarketGood = fc_ou_turret01_mark03, 26, 0.400000, 10, 10, 0, 1
MarketGood = fc_ou_turret02_mark01, 6, -1, 10, 10, 0, 1
MarketGood = fc_ou_turret02_mark02, 16, 0, 10, 10, 0, 1
MarketGood = fc_ou_turret02_mark03, 26, 0.400000, 10, 10, 0, 1
MarketGood = ge_s_thruster_04, 6, -1, 10, 10, 0, 1
MarketGood = missile01_mark01_ammo, 0, -1, 50, 50, 0, 1
MarketGood = missile01_mark02_ammo, 2, -1, 50, 50, 0, 1
MarketGood = missile01_mark03, 10, 0, 10, 10, 0, 1
MarketGood = missile01_mark03_ammo, 10, -1, 50, 50, 0, 1
MarketGood = missile01_mark04, 22, 0, 10, 10, 0, 1
MarketGood = missile01_mark04_ammo, 22, -1, 50, 50, 0, 1
MarketGood = missile01_mark05, 30, 0, 10, 10, 0, 1
MarketGood = missile01_mark05_ammo, 30, -1, 50, 50, 0, 1
MarketGood = missile02_mark01_ammo, 0, -1, 50, 50, 0, 1
MarketGood = missile02_mark02, 2, -0.200000, 10, 10, 0, 1
MarketGood = missile02_mark02_ammo, 2, -0.200000, 50, 50, 0, 1
MarketGood = missile02_mark03, 10, 0.200000, 10, 10, 0, 1
MarketGood = missile02_mark03_ammo, 10, 0.200000, 50, 50, 0, 1
MarketGood = missile02_mark04, 22, 0.400000, 10, 10, 0, 1
MarketGood = missile02_mark04_ammo, 22, 0.400000, 50, 50, 0, 1
MarketGood = missile02_mark05, 30, 0.750000, 10, 10, 0, 1
MarketGood = missile02_mark05_ammo, 30, 0.750000, 50, 50, 0, 1
MarketGood = missile03_mark01_ammo, 0, -1, 50, 50, 0, 1
MarketGood = missile03_mark02, 6, -0.200000, 10, 10, 0, 1
MarketGood = missile03_mark02_ammo, 6, -1, 50, 50, 0, 1
MarketGood = missile03_mark03, 22, 0, 10, 10, 0, 1
MarketGood = missile03_mark03_ammo, 22, -1, 50, 50, 0, 1
MarketGood = missile03_mark04_ammo, 30, -1, 50, 50, 0, 1
MarketGood = cruise_disruptor01_mark01_ammo, 2, -1, 50, 50, 0, 1
MarketGood = cruise_disruptor01_mark02, 26, 0, 10, 10, 0, 1
MarketGood = cruise_disruptor01_mark02_ammo, 26, -1, 50, 50, 0, 1
MarketGood = torpedo01_mark01, 10, 0, 10, 10, 0, 1
MarketGood = torpedo01_mark01_ammo, 10, -1, 50, 50, 0, 1
MarketGood = torpedo01_mark02_ammo, 30, -1, 50, 50, 0, 1
MarketGood = mine01_mark01_ammo, 0, -1, 50, 50, 0, 1
MarketGood = mine01_mark02_ammo, 2, -1, 50, 50, 0, 1
MarketGood = mine01_mark03, 10, 0, 10, 10, 0, 1
MarketGood = mine01_mark03_ammo, 10, -1, 50, 50, 0, 1
MarketGood = mine01_mark04, 22, 0, 10, 10, 0, 1
MarketGood = mine01_mark04_ammo, 22, -1, 50, 50, 0, 1
MarketGood = mine01_mark05, 30, 0, 10, 10, 0, 1
MarketGood = mine01_mark05_ammo, 30, -1, 50, 50, 0, 1
MarketGood = mine02_mark01_ammo, 0, -1, 50, 50, 0, 1
MarketGood = mine02_mark02, 6, -0.200000, 10, 10, 0, 1
MarketGood = mine02_mark02_ammo, 6, -1, 50, 50, 0, 1
MarketGood = mine02_mark03, 16, 0, 10, 10, 0, 1
MarketGood = mine02_mark03_ammo, 16, -1, 50, 50, 0, 1
MarketGood = mine02_mark04_ammo, 26, -1, 50, 50, 0, 1
MarketGood = mine02_mark05_ammo, 30, -1, 50, 50, 0, 1
MarketGood = ge_s_repair_01, 0, -1, 100, 100, 0, 1
MarketGood = ge_s_cm_01_ammo, 0, -1, 50, 50, 0, 1
MarketGood = ge_s_cm_02_ammo, 2, -1, 50, 50, 0, 1
MarketGood = ge_s_cm_03, 6, -1, 10, 10, 0, 1
MarketGood = ge_s_cm_03_ammo, 6, -1, 50, 50, 0, 1
MarketGood = shield03_mark08_lf, 26, -1, 10, 10, 0, 1
MarketGood = shield03_mark09_lf, 30, -1, 10, 10, 0, 1
MarketGood = shield03_mark10_lf, 30, -1, 10, 10, 0, 1
MarketGood = shield03_mark08_hf, 26, -1, 10, 10, 0, 1
MarketGood = shield03_mark09_hf, 30, -1, 10, 10, 0, 1
MarketGood = shield03_mark10_hf, 30, -1, 10, 10, 0, 1
MarketGood = shield03_mark08_fr, 26, -1, 10, 10, 0, 1
MarketGood = shield03_mark09_fr, 30, -1, 10, 10, 0, 1
MarketGood = shield03_mark10_fr, 30, -1, 10, 10, 0, 1
MarketGood = ge_s_battery_01, 0, -1, 100, 100, 0, 1

Thank tou very much!!!You have my best gratitude.Thanx

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