My originals were stolen in the early 80's, and my insurance got me the reproduction set shortly after. I'm trying to remember the name of the company, they did small batches when they had enough orders so it took a while to get them. They are/were located in Ca. the replacements are welded. I had no problems with tire mounting or balancing. I put the tires and rims in storage for a long time and when getting them out the chrome/steel part did have a bit of surface rust, the aluminum lightly oxidized. I used the aluminum foil method on the chrome and it did an OK job of bringing the shine back with minimum pitting.
I have a set of repro Polyglass tires on them and only use them for judged shows. Otherwise, I run a set of 17" Legendary Wheel Co. GT9 wheels.