I'm not familiar with an S850 tiller, but I purchased a complete set for a 6' Kubota gray market tiller from Fredricks Equipment, Inc., in Hartselle, AL, when I lived in Mississippi. They are still in business as I just called them to be sure. Their # is (256) 773-9951. If they don't have what you need, contact Service Dept. Vic here on OTT. He can supply tines for most tillers. Good Luck!
Vic i need 3 of them. I was gonna replace them all because they all seem to be worn. But there are 21 of them and thats $400. WOW yea that ain't gonna happen!!!