If you are realy frugle you can bore the wheel cylinders to the next size rubber cup and turn new pistons from new stock. I did this on a 46 1.5 ton 5 yrs ago with no problems. I made a simple jig to hold them bored and honed them on a Bridgeport mill. All four cylinders and pistons were turned in one afternoon. Total parts cost was about $10 for new rubber cup and piston stock.
