I bought 3 o-rings from Rocketseals(www.rocketseals.com/303-777-7024)
2x 2-110 EPR
1x 2-118 EPR
These are brake fluid safe, and should fit the hill holder. I make no promises, but they worked for me in an '87 Brat rebuild. Rocketseals is in Denver, and the parts cost me $1.40. I asked about phone orders, and they said they do phone orders and ship. The red circles indicate where the seals are that you are replacing.
Since I couldn't find any threads on this, and my hill holder was leaking, I decided to tear it apart today. To rebuild one, you really only need 3 o-rings, and 2 are the same size. The pictures should tell most of the story.
Pull it out of the car.
Remove the nut and cap on the spindle.
Remove the snap ring with the appropriate tool.
Remove the front cap with a large allen wrench/socket.
Remove the circle spring thing and ball bearing.
Remove the plastic insert.
Remove the metal rod with spring.
Remove the cam spindle(there are o-rings on it, so it might require force).
Replace o-rings, and put it back together in the opposite order.
Clean and disassembled:
Edited by Speedwagon, 15 March 2013 - 10:25 AM.