I did the one cover with hog rings and pliers from NPD, and they worked fine. The only difficulty was that I bought only one size of hog ring (small) but also needed longer for the seat seams. Instead of running back to NPD I pulled out a roll of mild steel wire that I use to bind rolls of snow fence with in the off season. I bent, poked, pulled and twisted my own wire ties.
Vikki 1969 Goldenrod Yellow / black 400 convertible numbers matching