Beware & know who you are getting your rockers from, most of the used stuff is used up. After you get them, sent them to T & D and have them checked. They can and should be rebuilt (if needed).
After wasting a lot of effort I ended up ordering a fresh set and used the old bars (which rarely go away).
Jim Wright had some before Mr. Breyton closed shop, sorry I don't have his number.
Pictured pair of heads are interesting, you don't see many of them.