Take a look at a 501C too. I think they're by far the best bargain because they're a slightly newer model (came right before the 501CM) and come with an acute-matte screen. Purchased separately a standard acute-matte screen might cost about $100, unless you get a great deal on ebay. I had a 501CM for a while and honestly I preferred the 501C. Of course, I don't use use long focal length lenses, in fact, I only use the 80mm.
But definetely, definetely, definetely get an acute-matte screen. It really is a world of difference and makes composing not only so much easier, but more fun.
I do agree with the previous seller too; put your money on the glass. My justification for moving from my Bronica S2A (which used great Nikkor lenses) to the Hasselblad was that Zeiss makes the best lenses. However, buying a Zeiss lens with marks all over the coating and scratches is definetely not going to produce better photographs than one of those Nikkors in perfect condition. So, if you're going to buy a Zeiss, buy a perfect one.
I actually have an almost-mint 80mm C lens if you're interested. It's actually a late C lens, which means it's exactly like the CF (it looks like a CF lens, not the normal C lenses) lenses except for three differences: No coupling lever (so you can turn the shutter and aperature rings together), no "F" setting (so you can use it on a Hasselblad with focal plane shutter, unless you use "B") and all the markings on the lens are white (as oppossed to orange, grey and white). Optically the lens is exactly the same as the CF lens.
I'm not sure how much you want to spend on a lens/kit, but my asking price would be $460 plus shipping. The reason I'm selling it is that I really like the aperature-shutter rings being able to be coupled together, so I bought a CF lens. If you don't think you need that feature then this might be a good change to get a very nice lens in great shape at a low price. If you're interested feel free to PM me with you're e-mail address and I can send you some pictures.
-Brent