You can install a single turbo kit on your original GE engine, or you can swap in a GTE engine which will include the stock twin turbos (or you could also upgrade to a single turbo). I would highly recommend finding a shop that you trust to guide you on this project and provide the parts you need, and optionally to also do the work for you.
If you are looking for engine swaps, we have an amazing resource in Philly at
www.elitejdm.com who imports a ton of JDM engines and offers the best quality in the business.
If you are looking for labor or parts, there are many vendors on TST that can help there. Check out the vendor section of the forum to see who you might like to contact regarding that, or maybe you can get some recommendations from other forum members.