Enion,
The tools and techniques used for making 'things' (any kind of thing) are really very fascinating to me, and often informative. This forum has been a great boon to my own work with all the differing ideas and techniques that have been shared here.
Fortunately I haven't yet experienced any cramping in hands or fingers when sculpting, but I can see how it might become an issue trying to hold tight a thin and short tool, like an un-mounted needle.
Buttons and small rivets seem much the same thing then.
I still think that the PTFE idea is an interesting one, though for me it turned out to be too different from what I am used to. Besides, I've never really had trouble with putty sticking to my tools so long as I'm diligent about keeping them clean and dipping frequently in talcum powder (Baby powder really because it is more common and cheaper than the industrial stuff).
You must have missed seeing the tools for $2.65 on the site. Perhaps those other more expensive ones are a better quality as you suggest, but perhaps not too great at only $6.65 each. Though I've purchased from this company before I have not ever purchased any wax carvers so I can't speak to the quality. I saw a set on Amazon for $19 and change, but it had something like three dozen tools in it. I can't imagine that the quality of these would be too great. In the end I really like your idea of using the cheaper tools to create your own from, with refined edges and modified profiles.
Thanks for posting,
Ray