Robert, it sounds by your description that you have a late 70's model, made around the time the Olympia One was in production. Correct?
If memory serves right, I believe these earlier CB's first used the same motor in the 1205 & Golden Jubilee, then the larger Super J motor. You could always find a good used Super J motor to install. I would strongly suggest picking up a set of carbon brushes & a armature seating stone, though, considering the age of those motors the carbons will be down to next to nothing now.
One other option you could do, if you want more power, is to buy a Ametek double stage replacement motor. Most vac shop distributors sell Electrolux motor mount kits that include the rubber seal & metal plate to take the place of the original Electrolux motor mount. The Electrolux motor mount can't be used, though, since their motors & motor mounts were a little unique to them, & not industry standard. Sure, doing this would make the vacuum non-original, but if you're not a vacuum collector, & you're just a regular user, I'm sure what you're really concerned with is getting your CB back in working order.
I would also suggest, if you haven't already, that you check the carbon brushes in the motor you already have. It could just need a new set of brushes & a armature seating stone to seat them properly.
Below in the link is a Electrolux replacement motor kit for the plastic body canisters, with Domel motor, mounting plate & seal. This particular mounting plate & seal is what you need. However, I would suggest buying the motor mount & seal separately & using it with a Ametek 116311 motor for TriStar CXL vacuums, Ametek double stage motors are much better quality & longer lasting than Domel's double stage motors.
Best of luck to you.
Rob
https://www.johnnyvac.com/en/motors...otor-assembly-with-adapter-electrolux-ap-z999