Something like the old Xpan film camera for $3500 or so? Even $4800 may be doable.
...
Yes, i know about stiching. But I'd rather have it in one shot.
If the question is about cameras like the XPan that record the whole image at one moment, rather than with rotating mechanisms, then probably the dominant issue is that this would require a custom sensor in an unusual, low-volume shape, whereas with film, perfectly normal rolls of 35mm or 120/220 film can be used.
Bernard has a good point too, that the lenses for cameras like the Xpan send light to the edges of the frame at a very off-perpendicular angle which film can handle but normal sensors cannot, but once the sensor is a custom design anyway, a sensor maker like TrueSense (the former Kodak sensor division) could probably hande that with off-set micro lenses as on the sensors that Kodak made for Leica. Or a lens with a design more like a modern SLR wide angle lens could handle this better. However, adding a custom lens design also pushes the price up.
On top of all that, even though the desire to avoid stitching is understandable, the fact that
(a) panoramic crops from a camera like the D800 probably about match the IQ of the Xpan and
(b) stitching is so much easier with digital than with film
have surely reduced the number of people who would pay for such a camera, which hurts the economies of scale when there is a large sensor development cost to recover, which further pushes up the retail price needed to break-even, which depresses sales volume even more ... the vicious pricing spiral that has prevented so many nice "special interest" film camera options from making the transition to digital.