[Vwdiesel] Wastegate not working, overboosting, kkk turbo

[Derek]

Car is a 1995 Getta ( not a typo ! ) TD

Well, after fixing the pressure lines that run from the wastegate to the turbo and the intake to the fuel pump, I discovered that my boost gauge would do an impression of a fan if it weren't for the stopper. I checked that the gauge reads correctly so I moved on to the wastegate. I discovered that it is leaking right where the rod exits the "can". So here I sit contemplating my options. 

Is the wastegate replaceable ?

Can I use an aftermarket one if it is ?

If not, what about a pop-off valve ( NOT a BOV, I do understand the difference ... )?