I have a pair of 20 year old genuine Koni's around the place somewhere too.
I asked my suspension guy for a price to service / repair them them , but although he does my Ohlins for $90- plus parts he wanted $185- plus parts for each Koni!
Ended up with a pair of fully adjustable piggy back TEC shocks for less than the cost of the rebuild and after a bit twiddling they work at least as well as the Konis ever did.