All I have found is 73 up doors. Drove 6 hrs to a guy's house that said he had a good door. When I got there he noticed it was 73 and up. That's my luck. My fender isn't terrible but needs several hours to fix issues. What is wrong with the fender you have and where are you located?I have a very fixable RF fender. I have not seen available doors in years. (pre '73) I may? have a piece or two of door side glass.
You might try Joe Vega, aka "azchevs" for the parts. He is primarily a 68-72 A body guy but sometimes has stray Nova / X body parts. Sierra Vista, SE of Tucson. Don't believe? he is on this site, but uses the "azchevs" avatar on the Chevelle site, the Buick site, etc.
Good Luck Dave S southern New Mexico