Large Threaded Balls?

Hi there,

I was wondering if anyone can tell me where I might be able to find large 
threaded balls for barbells - I'm prepared for internal or external
threads 
and will change my bar accordingly.

This is the closest I've found but not UK based :(
http://www.steelnavel.com/product.asp?ID=821&MID=42&MID2=1&A1=8&A2=11

It all started when I saw a new pic on BME titled 10 ga Ampallang with 3/4

inch balls.! I knew I had to either put a curved barbell in my PA or
upgrade 
to an aprydryva. I'm currently at 3.2mm but love the idea of having larger

balls (on the jewellery!) than then the barbell traditionally dictates.

All help and flaming welcomed! Thanks in advance

A ;)