I think a market exists, possibly in the tens to few hundreds over time (with proper marketing, etc.). Combine that with a fresh chain option, again, and builds wouldn't surpass the trans capacity as easily.

I literally bought my Regal from the guy I built it for, because I wanted to have the transmission build, including GM Racing Torsen, 1" chain set, and Raybestos Blue Plates... all of which are now unicorns in the 4T65e market.