I have a few IP labs in stock, ready to be made into Polaroid Backs. I’ve listed them all under the Polaroid Film Back for Mamiya RB67 (only) – itype, type 600, SX70 film page, but I can build a MUP/P600SE back instead, just add it in comments.
Also, I have quite a few separate RB67 kits ready to be assembled, these are JUST the kits, not the complete backs.
The lead time for any of these is about 4 weeks.