This is reminding me of those Amiga 4000 motherboard reverse-engineering projects, which have now borne fruit in terms of a digital schematic for the Revision B board as well as attempts at building new replacement boards like the A4000+.
Getting to that point took like $5,000 in donations just to get a working example reverse-engineered, though, and producing the PCBs can't be cheap. Then there's the matter of how the AGA custom chips are long out of production, likely requiring cannibalization from existing A1200 or A4000 boards. Not even those diehard Amiga enthusiasts with deep pockets can afford the sorta quotes that wiretap's hinting at for this.
Small wonder why retrocomputing is moving to FPGAs now; it's easier to work with those off-the-shelf than to try and convince a foundry to manufacture obsolete ASICs. Heck, you can get even better results if the Apollo Vampire is any indication.
It's far less likely to happen for IBM PC-compatibles, as they're cheap, common hardware with readily available replacements, or so the market would have you think. Even vintage Macs are relatively easy to find parts for, due to their sheer proliferation for something that isn't PC-compatible. Amiga, Atari ST, X68000, FM Towns, or anything Silicon Graphics, though? Sorry about your wallet.
