Jeff,
Have you tried making one out of a soda bottle? You make the plug the size and shape you want. Then follow a stuffing and heat shrinking process using a heat gun. For a Ringmaster canopy you could use either a 1 liter or a 2 liter bottle. There are other posts about this under the building category. (Use the seach function here and look for canopy.) There have been articles in prior magazines. If you want to go that route, there are guys here who you can always ask questions. And you don't have to worry about the cost of scrap--the empties are cheap.
If you feel you cannot tackle that, I can pull one from a profile plug that I have. I'd have to check to see how close it matches an S-1 part if that matters to you. I won't claim the optics will be perfect because the bottles aren't perfect to begin with, but for a sport plane, I have been satisfied in the past. You cover the cost of postage and we can make it happen that way, too.
There may be a source out there for profile canopies. I just have not looked. If so, someone else will chime in.
There is at least one profile canopy in the Brodak listing:
http://brodak.com/control-line-parts/canopy-cowls/mustang-canopy-j-roberts.htmlDivot McSlow