I would just add that I bought a P45+ back from "Mr. Rib" recently, it worked as advertised. "Mr. Rib" also got me a Hasselblad 555ELD to put it on.
Very much satisfied with everything.
I have a CFV-50 Hasselblad back for offer. Mint condition, approx. 1000 actuations.
Price is $13k (+ shipping + Paypal fee if you want to pay with Paypal). I am located in Europe, Poland. Local pickup would be possible of course.