You should be able to find one for $5K or less. The body when fitted with AE prism and film back feels very solid and is as beautiful to look at, as it is to shoot. You can even add a nice (but expensive) accessory battery holder/vertical grip (the MP-1).
CONTAX 645 DIGITAL BACK PRO
The best buy, if you can find one, will be a Kodak DCs Proback 645C - it has limitations - youn eed to work at ISO 100 to160 and forget about exposures longer than 2 seconds - buit for landscape and portrait work the (discontinued -just like the Contax 645 - bit for different reasons) the Kodak 645 pro Backs are great. The Contax 645 is a modular system with removable backs, prisms, and lenses. That didn't keep me from really liking using the Contax or thinking it was anything but a great camera - but superior? Nope. For 4X5 Large Format Cameras Digital Back Adapter Contax 645 Mount. The lenses for the Contax were quite nice but only marginally (if at all) better than the lenses for the H1. Having shot pretty extensively with a Hasselblad H1 and a Contax 645 last year both with digital backs, I just didn'yt see any superiority: the contax was heavier, went through batteries dfaster and the autofocus of the Contax was much slower and no more accurate.
![contax 645 digital back contax 645 digital back](https://dt-outlet.com/wp-content/uploads/2021/10/Screen-Shot-2021-10-28-at-12.44.40-PM.png)
Hasselblad is a business, not someone on the Jerry Springer Show, they are perfectly happy to sell you a product they make. This digital back provides 40Mp of resolution from a 44 x 33mm CCD image sensor. You can even add a nice (but expensive) accessory battery holder/vertical grip (the MP-1). This Mamiya Leaf Aptus-II 40 Digital Back is compatible with the Contax 645AF. Hasselblad is perfectly happy to sell you a $20,000 back for a Contax. The Contax 645 is a modular system with removable backs, prisms, and lenses.
![contax 645 digital back contax 645 digital back](https://d1rzxhvrtciqq1.cloudfront.net/uploads/images/listingimage/529110/image/thumb-e48720115e71f96b2a28134fecf484ce.jpg)
((recently merged with Hassleblad so don't expect too much support for your superior Contax.)