I saw cans for sale at a gun shop in Aix en Provence France in 2003ish. They had a selection just like you described, but aluminum. Most were 40-60 euros ($55-75 at the time) and were available on the shelf next to hearing protection.
I'm good with Aluminum too- I was just envisioning cheap and effective. Silicone liners for heat resistance, heck, I imagine you could run some kind of plastic shell.
The money in this (
@DoglegArms ) is going to be in the cheap everyday cans that don't require a threaded barrel. I can imagine several kinds of "over the muzzle" attach devices that would allow for attachment of the suppressor. Of course the bore tolerances will probably be a little bigger than a thread mounted can, but I think through testing, you could probably find the happy medium between ease of attachment and decent sound suppression.
