The 503CW is still made, or at least its still available new. However, it has provisions for a digital back, and there was a 503CWD version produced at some point.
Small corrections:
- The 503 CW doesn't have provisions for a digital back. Just as no other Hasselblad model, except the 555 ELD (and you could have a 303 or 205 modified).
Hasselblad had been the 'target platform' for all digital back makers. Until Hasselblad decided to try to close their H-system for backs not made by Hasselblad, there was no back made (except by Rollei) that wouldn't work without a problem on a 'regular' Hasselblad camera, whether made in the 1950s or the 2000s.
- The 503 CWD was not a different camera, but a kit consisting of a normal 503 CW (though with different badge and chromed wind crank arm), an 80 mm lens, and a Hasselblad CFV 16 MP digital back. The kit was available for a short time, to mark one of many Hasselblad anniversaries.
So also no provisions for a digital back on the 503 CWD. There's no need for such provisions.
And a note about the lenses:
Yes, every V-system lens ever made will work on the 503 CW, provided it has a shutter in it. (The shutterless F/FE lenses will work too, but you will only have the 'un-timed' rear auxillary shutter to control the exposure. Works for times of about 1 second or longer. So not really.
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