Very top? or Top of the lower leg?
If it is leaking at the very top near bars, you may just get away with a new cap seal.
If it is at the seal on the lower leg, you will need to pull the forks and rebuild.
Service manual 50.00
Rebuild kit 10.00
Fork oil 15.00
Time, what ever you think your time is worth.
borrowed from gtrman66
Leave the gun. Take the cannoli.
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