Baer actually went to the trouble to develop a "web-application" for hub service parts. Here's the GM link:
https://baer.com/GM-hub-hubparts/
I'm quite confident they used a "blank" 5 on 5 that afforded the offset required for their needs. Baer has the information for sure I'd think but OP I'd think if you have a current set, a spare and the bearing information from yours you've got enough spares to last you the life of that truck.
Post the bearing information and let's check matches for those. That should be very easy. Nearly all inner/outer wheel bearings are done in sets. I can't imagine Baer changing up that aspect but it's certainly a possibility. There's many, many, many hub casting manufacturers out there, maybe very few left in the USA but there's a few.
Now if you're attempting to maybe source rotors that's likely a completely different story BUT I would think it could be done if you've the dimensions of the known fitment.