My 63 had a custom comfort seat but it was in such bad shape that I could hardly tell. The factory brochure pictures posted earlier in this post looked exactly like my seat, so I decided to have my seat reupholstered using the same pattern. I chose plain black vinyl instead of the original pattered black cloth to keep costs down and make clean up easier.
Here’s a video of my seat, BEFORE & AFTER.
https://youtu.be/6PWQsV7w0z4