It's a game folks. If you want the game to be fair (and fun) leave that armour at it's current price. If you want a cheap, and good thing, a CAU VI will be both cost effective, and also great.
Now, is the price logical? To cost twice as much than the ship you mount it on? Probably not. Hell, if it'd be me, I'd make it a billion, to have this round price figure. It's just a status-quo item