Info on 73 Duster

I have a chance to buy a 73 duster 318 all original except paint..interior is in great shape, auto,light rust in lower quarters (fixable) and some small wholes in truink, heat & A/C dont work, has 7 1/4 rear and comes with 8 1/4 rear, engine starts and runs great and is driveable, they are asking 3000. what do you guys think??..thanks Bob