New gear box time?

I finally had time to put my car on stands and see why i was getting a grinding/juddering coming from the gear box, i decided to put some gearbox oil in to see if that made a difference and it did for a minute until it all poured out between the clutch to engine seal. I guess one of the inner seals has gone, can this be fixed? or should i look for a new new box to go on. Its my daily driver and i'm running out of cars to borrow so the quickest route is best. Its a 1992 gti cabby

Where did you put the gearbox oil in? Sounds like you put the oil in the wrong place.........