The 13/14 base GT500 wheels that I just put up pics of after being powder coated in another thread I found locally a while ago for $900 a set and they were new in box. It was a rare find and price but they still sell these Shelby GT500 wheels at MW wheel and tire for $379 each so you should be able to get some decent money for them or move them quickly for a lower price.
Base wheels were the bomb when the Trinity's first came out. I liked the base wheels better than the PP wheels. I even bought a set complete with tires from a member here and used them for my track days at my home track (Mosport).
After a year and a bit using them I sold them and got the Forgeline wheels that I ran on my car for 5 years or so until car was traded.