Ray: the M-117 was to have incorporated a lot of plastic in its construction to control weight. With the 100hp RR Continental, it was to be a fixed-gear, 2-seat trainer selling for just over £3000 (according to Flight).
Jens' illustration shows the tonier 145hp version with constant-speed prop. The retractable-gear version was to sell for £4500. A fixed-gear option was to sell for £4000-£4500.
Of course, the M-117 emerged as the all-metal Beagle Pup with an upward climb in horsepower.
http://www.flightglobal.com/pdfarchive/view/1961/1961%20-%201160.html
http://www.flightglobal.com/pdfarchive/view/1961/1961%20-%201268.html