Need to get rear quarter patch panels. Where's the best place to get them?

With engine and transmission done, I decided to start on body stuff.

Got rust-through in the LH rear quarter and about a 1/4" of bondo. Decided it's be best to just cut it out and replace it.

Got two questions:

First, my car is a '72 dart custom 4-door. Are the 2-door quarters the same? (I'm guessing they are, but wanna be sure.)

Second, Where is the best place to get them? Lowest price I've found so far is Edit: Nevermind, they didn't have dart quarters.

Thanks in advance for any advice!

~Rev.