I would gather a a lot of plow shops carry like items that can be either a direct replacement or, can be modified to work for you,
I know I used to go thru a lot of like items and had a local machine shop make me some in the off season for a fraction of what the dealer wanted, using hardened steel as the shoe, lasted as long or longer, I even had some made to be thicker, which gave me more time between having to replace them!
Now this was all Pre Covid, and back when the world of things not costing crazy prices,
so take my info with a grain of salt if you shall, HAHA!
you have to consider this BS over priced world we now live in anymore
if you old one's are in good enough condition, you might also be able to just have a good machine shop weld on some harden steel to the shafts you have now! and have shaped ion a circle or what ever shape you wish them!, not sure again if cheaper than trying to find OEM though??
lastly, this NH part # should be a direct replacement too, but NOT any cheaper or in stock pending where you look now, but gives you a direct option to look for
SKID, SHO
www.newhollandrochester.com