32" 455 Tiller problems

[Guest]

I have a 32" model 455 tiller, for my Sovereign 3012 tractor, but at least one sprocket is worn so bad, the #50 chain is so loose it has chewed through the case. I assume that the only way to repair this is to replace the worn sprocket PN 105195, but Simplicity no longer supplies it. Any suggestions? Also anyone have any thoughts on what to use for the tine shaft bearing shields, my are very mangled. PN 105237, no longer supplied either. Another tiller may be the next best thing, anyone have one for sale. I am in Connecticut. Thanks, FredT ohc6@earthlink.net