I have had so many scrap mowers given to me, I just go raid my pile, however on non-self-propelled lawnboys the wheels can be generic, just get the right size, and offset. I can get them at the local Ace Hardware store.
#4
unclelee
If you are looking for the green mag style, you may just have to watch eBay.
The white ones are a lot easier to find.
Lee