Late Captain's Chairs Armrests
Note the distinct change in shape & size for the last design. Viewed from the top, the front is noticeably pointed, as compared to all older designs, meaning upholstery is not interchangeable across the years due to fit.
For new upholstery, check
http://stores.ebay.com/RichmondAutoUpholstery?_trksid=p2047675.l2563 
