I thought there was a compilation on the board fir parts sources, but the best think I could find in a relatively short time period was under “Website Links”. I still think there is something else available.
I’ve had good luck with florin tractor (status?), regal parts, and our own gemdozer over the years. Harry Brandt comes up with stuff from time to time and Christenson (spelling) machinery. There are others.
Keep safe!