Multiple single.php template for the same post

Hi there!

I’m currently working on a project where I need to display the same post in two diferent ways. Here is how it should be:

Post 1 is in categories a and b.
Post 1 can be listed using the category-a.php or the category-b.php templates.

Is there any way to display the Post 1 using single-a.php, when the user clicks in the category-a.php list, and to display the same post using single-b.php when the user comes from category-b.php?

I’ve thinked in passing some variable to the permalink structure, but this may be a little tricky, and I’m not sure if that’s the best way to aproach this. Maybe WordPress has a better way to handle this, but I don’t know any, some help would be really apreciated!

Thanks a lot!