I’ve seen a few people on this forum who have 17T1’s or 19T1’s without a back. A good reproduction can be made inexpensively with minimal tools and a lot of patience. I don’t know of anyone (other than me) who has actually made one, but if you’re interested, here’s a link to a “how to make it” discussion:
http://www.videokarma.org/showthread...ferrerid=70422