Nice Fork RST Hi 5 Double Crown.
Stanchions are TOP
Function : TOP With Full Travel
Travel : +100mm
Elastomers : TOP
Cosmetic : some paint chips.
Steering tube : 21cm 1"1/8
That is an RST HI5, they were recalled back in 1999 - 2000. Contact RST at RSTsuspension.com they may still honor the recall and set you up with a brand new fork