Thought so. Isn't manufacturing and looting missiles too much of a hassle though? I didn't sell or use them at all, but there's at most 80 missiles total in stores at all bases.
No, I didn't find it that much of a hassle. There was not much else to do except disassemble and build interceptors, really, in my production base. Other bases took care of EP ammo, armours and weapons. And you only really need to use the missiles against Gunboats and up (if you're up to date on interceptors), so if you don't mind doing a lot of missions, you can maybe get the needed antimatter missiles from the downed UFOs.
It sounds like maybe you've been skipping out a lot of missions (by shooting everything to sea) or maybe you've just forgotten to sell that pile of 100 alien armours or something, and so you don't have enough money for laboratories and workshops and new bases.