Turbo Oil Seal Leak fixable?

My T25 stock turbo is leaking I believe...I have Oil coming out of my BOV and the oil pan is not overfilled...it was but I drained some and it still shoots out Oil...Would I be able to fix the oil seal so it doesnt leak? If so would I have to take the engine out or just the turbo? Or do I have to get a new turbo or have my current one rebuilt? How much does it usually cost to have a T25 turbo rebuilt?

Thanks