I saw the advert at the top of the page and ordered some button head screws from
http://screwz4rc.co.uk/
They arrived yesterday and I must say they are better quality than the last lot from ebay. (can't remember who the seller was). They are more shiny and the socket is a bit deeper and a better 2mm fit.
I will be ordering more once I get a list together. Thanks Brian for such a good service.
Hope this helps.
P.S. I've used Modelfixings for imperial screws too and they were also good and quick.