With a bit of help from a post on Quora, I found that Rickey had a record of 322-69 stealing 3rd. This is a success rate of 81%, which is exactly the same as his overall 81% success rate. But a rate like Rickey's in MLB not a functional possiblity for in SOM. The one base Rickey wasn't effective at stealing was home. He went 4-8. But at least he didn't try it very often.
The Quora post pointed me to the fact that Baseball Reference has an advanced stats section on "Baserunning & Misc States" This gives the steal rates for the various bases, at least for players who performed after the leagues started recordig caught stealing. That's where I found Rickey's stealing stats for specific bases.
https://www.baseball-reference.com/players/h/henderi01-bat.shtml#all_batting_baserunningJackie Robinson was more successful than Rickey at stealing home, going 19-12 in the regular season. Actually, Jackie didn't try for home plate that often, either, but it's an exciting play and his steals of home definitely made an impression.
On a personal note, I wasn't much of a hitter in my Babe Ruth League days, but I was a fast runner and pretty good at base stealing, if I could find a way to get on. I remember that once I stole second then third rather easily--at that level most pitchers hadn't learned how to hold baserunners And then my third base coach was egging me on to try to steal home. I took a look at the setup and said to myself, "There's no way I'm trying that!" It's a pretty scary prospect. You've got to somehow beat the pitch to home plate, which invovles getting a BIG lead on the pitcher, since nobody traveling 90 feet can outrun a fastball traveling 60 feet. Then there's the risk of getting hit by the pitched ball, or of getting clobbered by the catcher as you dive into the plate head first, or of being decapitated by the hitter when he knocks a drive down the third base line. It was a mark of Jackie's daring that he was willing to risk all of that. I wanted no part of it, and after just one look, I immediately swore off stealing home. Stealing 2nd, definitely. Still third, sometimes. Stealing home, never!