I don't usually buy from this place.
Here is a motor from them. I will find one cheaper for you. Stand by.
BetterIt is a VDO PM351. (Siemens).
AutoZone has it for $14.95. Some stores have it in stock, some may charge ship.Search that PN and buy where it's best for you. Lot's of places have it. This Part Number is assuming your heater is original era. The good news is it seems you just clamp it on, so don't care too much about mounting studs or motor length or shaft length.
This motor is reversible. Red to hot, black to ground is CW. Reverse the wiring for CCW. You will need to find a switch.