Dr. Quill would definitely not sell AEGIS weapon technology. But it could have been hacked from his systems. Or he might have deployed it himself (as an orbital mining system, as an orbital energy transmission system, as an orbital asteroid defense system) and had it taken over / compromised / confiscated / blackmailed away by AEGIS.
Bringing Dr Quill into this is a nifty idea. Even if it’s totally backstory.