@pkillo
Recommendations on parts sources (preferably in the US) will also be appreciated.
I recommend CraigsList for used SCSI stuff, particularly external enclosures and CDROMs. You can pick this stuff up for a song there. What is junk to a Mac or PC owner is gold to Amigans.
Incidently, I just built a system over the past year from a stock A3000D that I bought for 'cheap'. As Ellis stated, building the system cost much more. I bought a WarpEngine, CV643D & X-Surf and several SCSI peripherals - and still building. I guess that is half the fun.
I am also looking for a Rev 8 SCSI chip but I am not sure what benefit that it would add.