The guy with the Marlin was cool, he has a '67 Charger too but he needs to rebuild the 383 it has. The Marlin is a 6 cyl, factory disc brakes, which you can't find, but brakes off a AMC Sprit bolted on.
everything on that whole car is going to hard to find. I had a chance to buy one for 800. but I didn't do it and the guy couldn't sell it because parts for those make hens teeth look plentiful.
You would almost have to buy two complete ones as a pair and build one out of them otherwise good luck