Standard Magneto in Chicago should have the coil and possibly the retaining clips.
http://www.standardmagneto.com/
I replaced my coil a few years ago and got it from a marine parts dealer. Some old Mercury outboards use the same coil.
http://www.autoboatmainetruckpartsga...-Bendia/Detail
These may be the correct retaining clips but I'm not 100% sure.
http://cgi.ebay.com/ebaymotors/?cmd=...K%3AMEWAX%3AIT
Hope this helps, Bill