I think the Harvey K-Chuk dimensions were pretty much standardized. At least one of the companies mentioned can make these up without starting from scratch; may even have a set in stock.

I've only dealt with RCBS on wildcat dies and it was a long time ago. I had three or four sets made. You only had to send them three fired cases. Dies were perfect every time, but I heard they stopped doing this.
Whether or not that's true, I don't know.

Be wary of old loading data, and most of it is old. The late Kent Bellah, well-known gun writer from Saint Jo, TX did a lot of work with this cartridge, but you probably know all about that if you have an interest in the K-Chuk.