Unfortunately the hose clamps will not do, neither will anything at the
url above.
I did look for curtain rings at some point - but they tend to be too
small in D.


To try again - imagine 2 x 3.14 x 2 = ~12" long drill rod, 1/8 in D.
Now roll it into a perfect circle , heat treat and bingo - you got just
the thing I
am looking for.

Or, if you want to skip the heat treating part, imagine rolling 12"
length of music
wire of .100-.125 in D.