If I'm remembering correctly, 4,000 of these were struck in bronze and 200 in silver by the US Mint in Philadelphia. I don't have my references handy at the moment, so someone else should be able to correct me if I'm wrong. Even with a relatively high mintage in bronze, these are difficult to find. It took me forever to find mine!
It should be 1 5/16'' (or about 33mm as you say).
I know you're not concerned about value, but I will give you an estimate anyway. At the moment, I could see this selling for between $75 and $125. This price reflects the difficulty of locating one of these and the demand generated from the relatively new NCM references, Dean & Swoger.