Got the video card now.

As the 7800GTX 512MB still was out of stock and the 7800GT dropped quite a bit in price today at my local computer store I went for SLI with dual 7800GT.

About £40 cheaper than the elusive 7800GTX 512MB but quite a bit faster. After all im a cosworth owner so I had to go for the product with most bang for the buck.