Having heater problems

I'm working on a 1947 Ford panel and putting the original two speed 6 volt heater in. The problem is the heater motor is burned up and I need it rebuilt or replaced. I'm converting the truck to 12 volt but the original heater has to stay so does anyone know if there is a place that rebuilds them or has a 12 volt replacement to go in the original heater box?

Thanks Jr

 

Here is what I did on the car,
I took the motor out and took it with me to napa.
They have a book with pictures and dementions,We just matched it up with a new 12 volt motor,took it home and I was finished.
Hope this helps you
Russ