Nothing against China*, but if you're lookong for some alternative with Amiga expertise just try
www.dcecom.de. They have the knowledge, the maschines and the experience - at their faclities the GREX, PuP-devices (after P5 went bust), Pegasos I & II, SX-32, Efika, etc. have been produced.
Maybe it's worth contacting them.
*) really not! I have mostly good experiences with Chinese products (well, there's also crap between, but there's also crap made elsewhere of course) and ppl.