Ohhh Boy...this could be a tricky one...[:@]
Some Saito rear bearings are a rather tight fit in there...and having lost the mass of the balls, retainer and inner race, it might be really difficult the knock the remaining outer race out by rapping it on a block of wood.

In past experiences, I have had to use a lot more heat on a few Saito engines to get the R. bearing out...
You might need to go higher in your oven temp?

Is there any way you can get in behind the outer race? Like say with a special tool made out of a narrow flat bladed screwdriver with the tip bent 90 * and ground thin? (know what I mean? )
Similar to the pic in Greybeards post #3 but go in through the backplate opening? Is there anything (any "lip" ) to catch on? You'd still need to use heat...and leather gloves of course.