Need help choosing a turbo

Since just about every manufacturer of a turbo kit for my car has stopped making them, I have to custom design myself a turbo kit. I am looking for a bit of help in designing my kit.

I want something with a quick spool up, ability to push up to 300hp to the ground if wanted, but only looking to push around 6 or 7PSI daily.

I own a 3.0L V6 if that matters to anyone.

I have done a tiny bit of research on this topic and was thinking of going with the GT28RS with dual ball bearings. Garret claims its good to up to 310 hp and the ball bearing should give me a quick spool. I just wanted opinions from others.

Thanks,
Joe