Those scarce and $$$pendy cork seals can be replaced with a piece of square neoprene O ring material- - - -cut at a 45 degree angle and super glued to the inside of the ball pivot collar. Trim the material to be a snug fit to the squared-off section of the ball collar, with the angled joint at the top of the pivot ball to minimize or eliminate any leakage. Then shim the ball collar to the back of the bearing retainer with a stack of gaskets to establish a snug, but not excessively tight seal to the pivot ball.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!