Wow, that's good $$$.
Even if you don't plan on keeping it for 10 years, I always think it's easier to sell and worth more if you have all the stock parts. Or at least the ones you can see or that matter.
But that's good cash! I *think* our stock turbo is the same as the GN's. And, turbos can be rebuilt fairly easily. So maybe it's not a big deal?