What you have described is common to most of the 30s, 40s, and 50s White Rotaries. Love your pics, excellent photgraphy, and nicely sized for those of us still on dynosaur dial up.
I've got 4 or 5 machines made by White. They are Singers contemporary and in some ways better than singer.
The drive wheel can still be had, and they're not expensive. I put half a clothes pin between the motor and the motor bracket to hold the drive wheel off the hand wheel. That way it doesn't flat spot.
Joe