Hey Turbo ................. Ok yes the lubricant you put on there did the trick for you.... Graphite is a go to also..... It's a must though to take the gear off and clean everything well.........
I do think that the starter from the Snapper Briggs will work, Briggs made 2 different starters in that era.... One weak starter for the ACR cam engines and a heavier duty starter.... A quick glance at both will tell you if it will fit....
Both engines are in the same size class..... Yes hold onto that blown motor.... Parts do come in handy.........
Numbers would be great to post so we can look them up for you ............
Let us know Mon Ami ~!~!