the quest for 5.6X61 vom hofe brass continues

To make a long tedious story short, the chamber for my 5.6X61 vom hofe is tighter than what RCBS made the forming dies to. The dies are made to spec, my chamber is not.Thus i am now needing to cast my chamber and send my dies back to them to get them adjusted to my chamber.
I know Midway has Cerrosafe Chamber Casting Alloy, but is there anywhere in the Richardson/Plano/McKinney area that might have it locally?

I don't know about the casting alloy, but I just recently had a gun rebarreled and the chamber, and particularly the neck, were too tight. I finally decided to take it back to the smith and have the neck opened up a bit. So, a rework of the chamber is an option.

The last Huntingtons catalog I had showed Vom Hofe brass, you might try Old Western Scrounger.com