It just so happens that on Saturday I was at a small Model Engineering show and picked up a book entitlied:
"Building Stirling Engines without a Lathe", by Kjeld Hoejfeldt, published by Camden Miniature Steam Services.
This is a very interesting little book which shows how to build Stirling engines from junk - in fact they have a distinctly mechanical TV look about them - using parts of scrapped VCRs etc.
There were some homemade Stirling engines on show which worked quite well and also more professionally built units which generally started at over 100 GBP - though looking at one of the catalogues I picked up there is a starter kit listed at 34 GBP.
According to the book - 200 or even 300 RPM is quite possible on the homemade engines which implies gearing would be required to drive a Nipkow disk at a sensible speed. The professionally machined units/kits can manage 10 times that amount and conceivably might allow for higher FPS.
Thinking about actually producing a working TV system I would have though that a camera/monitor would be the simplest option - or maybe a close circuit system with 2 Nipkow disks driven from the same line shaft.
I may yet get to build a Stirling Engine - but in many respects the real acid test of this system is not concerning the motor drive (which certainly can be solved) but whether fibre optics (or even old fashioned glass rods) can be sensibly used to transmit the light - without any sort of amplification.
Roland.