I would try replacing it from the outside like everyone agreed, but if it only recently started leaking, i bet you've got a bent shaft that will need replaced.
Same thing happened to me, started leaking at the seal so i replaced it. Still leaked so i replaced it again... still leaked so i yanked the clutch and pulled the shifter out and it was banana shaped.
So don't be a dummy like me if it still leaks, you've gotta check your shaft!