A: Yes, the E986J-CTN is suitable for wet locations
A: Conduit bodies up to 2 inch are UL listed. Listing refers to the product, Code usually refers to the National Electric Code. The NEC is a guide to the use and installation of products. So it would be up to the installer to be sure the application and installation of the product meets code. As for why so inexpensive on Ebay - that is completely dependent on the seller.