Nick Zentena said:
The old postcard cameras are pretty close to 4x5 and tend to be cheap. Just takes a little effort to liberate the lens from the camera. Or didn't Polariod make some larger cameras that no longer have film?
Postcard format (3 1/4 x 5 1/2, approximately -- 122 roll film, or "Postcard" sheet film) usually used a 165 mm lens which will easily cover 4x5. Many of the 135 mm lenses used on 9x12 plate cameras will cover 4x5 without movements (Tessar will, just), and you can often find these cameras without ground glass or plate holders, but with (useless) film pack adapter and suspect bellows for $10 to $30 -- with good glass and shutter needing only simple cleaning. The 9x12 are usually cheaper than the postcard cameras, mainly because they're a lot more common. Even the cheapest lenses sold in these will do a fine job stopped down to f/8 or f/11, without movements, and most would stop down to f/32 (I have one shutter, with f/4.5 13.5 cm Tessar, that stops down to f/45). You'll sometimes find a 150 mm or even 165 mm on a 9x12, and these lenses will cover 4x5 nicely and allow for a little movement.
Removing these lenses is easy -- with the camera folded, the retaining ring is readily acessible through the camera back, and once it's started you can open the camera and hold the shutter from the front while unscrewing the ring the rest of the way. Mind you, I'd hate to see someone pulling the lens and shutter off a usable plate camera, but one that's in junk condition is another story entirely -- and the shutter and glass are likely to be the best parts of one of those.
The larger Polaroid roll-film cameras (took Type 47 film) made a 3x4 format print, approximately, and most have semi-wide lenses in the 110-120 mm range (the later Model 180/185/195 pack-film cameras made the same size images with a 114 mm Tominon); the Ysarons in the older cameras will cover 4x5 without movements, apparently (judging by the number that are converted), but I doubt the 114 mm Tominon will.