Turbo aside, the engine was the same as the one fitted to vauxhall astras (it may have been from isuzu).
If you have the siezed wastegate problem, they usually fit a new turbo, quite often under warranty.
If it were mine, I would either stick the wastegate shut and fit a boost gauge to monitor the boost, or see if you can fit a different type of wastegate valve like a poppet valve, or see if you can source an alternative turbo, preferrably watercooled as it is the heat/moisture combo that causes the problem in the firstplace.
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