Take a look at the bucker seats in an Isuzu . Remove the headrests(they look bad in an old car) and they should look and fit very well. Had a pair in my 37 tudor and they are very comfortable. The other seats that will work are the early VW.
If you want a bench seat take a look at the second and third seats in the mini vans like Aerostar, Windstar, Caravan, etc. The best thing to do is take and measure the existing seat and then go to Pick and Pull with the measurements. You can buy a nice seat for $50-60 and they usually have good upholstery.