I happened to stumble on a bunch of 3 Ring Binders (which is, in Germany, not easy - probably us Hârniacs are the only folks that actually use them).
These Binders are around 50% thicker then those provided by CG. Both HMC and HMG fit pretty well into one.
They are plain black, overall product quality is a bit less then those provided by CG, but they are still good quality in new (if a bit dusted) condition.
After providing for my collection and future needs, I still have around 30 to spare. If somebody is interested, drop me a line for prices.
I would send them from Germany, so no toll problems for EU members.