Tough thread to find today. Had I not known "HOG" had posted to it I likely wouldn't have been able find. I looked. Maybe the original "TOPIC" wasn't appropriate but "OFF-TOPIC"? C'mon - it's a car part. It resided there for nearly a week(6 days), I spotted it I believe yesterday AM.
With and without a tone-ring kinda sorta seems maybe FOMOCO for originality but here's a very generic illustrated buyers guide that you can browse to find maybe something "similar" in construction. Does you hub use a single bearing (meaning spindle would be heavily modified) OR does it use OE/GM inner/outer bearings to spin on? If a single bearing maybe identifying just the bearing first. Do you have one apart? Sounds like maybe you've no need now if the "bartered" set-up is in hand.
The 5 on 5 2WD GM configuration was done maybe specifically using a casting of a similar hub that gave them (Baer) the offsets that they needed for rotors/calipers already used.
This buyers guide is BCA/Timken numbered and there's references to OE/manufacturer also.
http://www.0086parts.com/auto/product/wheelhub.pdf
I thought maybe you had revisited, deleted your thread and posts after it went away also. That would have been ODD I thought. Maybe a "MOVED NOTE" to have redirected the thread might have been a reasonable effort.
"HOG" - You mentioned GMT400 specifically. Did you maybe have an affiliation of sorts with GM assembly there? The 53 model ECSB/ECLB (extended-cab) I believe was initially only assembled there. I did a plant tour in maybe '90.