Help With T3 Bb Turbo

[r3volt21]

i recently blew the compression housing seal when my wastegate actuator failed and was siezed shut, when i pulled the housing off i noticed some small cracks on one side of the plate around the turbine, I am unsure if this is a sign of housing fault or norm ware for an old turbo. The gasket that was sealing the housing was a cardboard gasket I thought there was meant to be a rubber O'ring there.

The internals seem to be fine, no oil around intake or exhaust side no smoke was blown and there is no shaft side movement or signs of turbine rubbing on the housing.

any help is greatly apreciated as it is my first turbo build.