Red copper is a fancy name for beryllium which is not a pure copper.
The long and the short of it is pure conductor connectors are not cheap. Furutech and Wbt are the best, and their cost reflect it, Cardas are good as well. With respectable manufactures, yes it is
real rhodium plating. I have a personal bias with WBT, every connector and binding post has been replaced with WBT AG or
pure silver with no plating, it wasn't cheap, and took me several years to do it, but was so worth the investment! I am also biased with Furutech as well, their GTX line of outlets are simply a work of art! First one I tried was like inserting a new component costing thousands of dollars! I now have 5 running my system. If you are going to stick with copper make sure its OCC or keep on looking.
Hope that helps.