Two questions, what is the housing that sets up on top of the motor (with the toggle switch) underneath called? Where can you get replacement parts for older Sears table saws?

You can try Sears Parts website, but if the saw is really old they may not have the parts. They have exploded parts diagrams which are real nice for identifying everything.

It's worth a shot anyhow.

Good luck,
WallyH

Sears 150 10 inch