Wheel Centre Caps

[djwilk]

Hi,
Anyone got an idea where I can buy blank centre caps? Or even the VX ones in the correct size? I am missing one (plain black, no emblem) and have tried looking on ebay but none of the sizes seems to match. I measured the existing cap as well as the hole and it reads 63 - 64mm external dia. and 54 - 55mm internal dia.

I know there were some HSV ones up and I placed a bid, but they weren't ideal for me anyway...

Thanks