I would start by checking out Ebay. Bear in mind that any plow you
find for that used is likely to be 10 to 15 years old or older as the
newset model of the chassis is now 16 years old. You might get lucky
and find one not that old for that frame style complete but not
likely. Plows cajn have a hard life and you do not want would well
beat because it can get expensive repairing them.  If you go to the
link below you will find links for most of the plows made and see what
is still overed for them if you find a used one that you can adapt to
yours if frame hitch is still in product. It will give you a general
feel of what models/brands to look for.

http://forum.snoman.com/viewforum.php?f=50
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