Like a lot of people I am now having window motor issues with my 07 Megane

The local garages want to charge a fortune to replace the entire mechanism where I think it will just be the motor itself. My first question is can I simply swap the rear motor with the front or visa versa?
Secondly can I just replace the motor or do I need the entire mechanism? (I tried to find it on eurocarparts but it only comes up with the entire mechanism).
Cheers in advance
David