Thanks to everyone who replied!
I'll probably end up checking out a hardware store the next time I go on an adventure. I did try ebay, and 2" was the biggest. Most were odd car rings the were 3/4" and 1/2" which doesnt really do me any good. I did find sites with a 4" rubber rings, but you had to have a min order of 500, or 1000, and I dont need THAT many. Hahaha.