These are custom made, and are as close to the size of original bushings as possible.
The outside diameter is 1.061 inches. The inside diameter is .875 inches. 
I have a New Old Stock main bearing housing with the original unused bearings in it, and I this is the apparent size.
As you can see, they have a beveled edge for the crank lobe side. The top one has an oil groove and is equivalent to original part #12720. The one on bottom has no oil groove and is equivalent to original part # 12752.
A model 92 single cylinder engine uses three bushings, two with the oil groove and one without the oil groove.
A model 72 twin cylinder engine uses one of each.

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