With four CC's, two 'O's and two 70's, I'm in need of tires. All of mine are dry rotted. I'm mostly wondering what to run on the front and back of the 'O's. The only affordable option I'm seeing in a 6-12 are ag treads, which I don't want. For something similar to what they came with, they want well over $100 each, which is too rich for my blood. Is there another option, or are tires that size simply becoming obsolete? The rears on one of my Model 70's have 23x8.50-12, which are readily available in a turf tread.