Wow that is actually pretty good for the stock turbo.  The turbo life
ussually has to do with how nice the owner is on the throttle.  Things
that you will notice when you turbo is going is loss of spoolup speed,
smoke comming out of the exhaust, and shaft play.  You can test for
shaft play by taking off the intake pipe and wiggling the compressor
shaft back and fourth.  Your price range can vary with what you replace
it with.  You can go with a used turbo for only about 150.00 or you can
go up too 1000.00 and everything between for an aftermarket turbo.  The
most common turbo to replace your current turbo would be a 16g.
Another thing you may want to try is testing your car for boost leaks.

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