Seriously don't overlook Derek Speare or Charlie Vasser if your in North America (http://www.**********************/Wheel-Adapters.html http://simracnwheels.com) or Brian Clancy in the U.K. (http://simracinghardware.com).
I'd much rather give my money to people within the community who are MORE than helpful in many ways and aren't trying to make a buck off you, but help you enjoy your racing. Seriously the prices are good for what you get, I've gotten cnc quotes for these adapters. IMO they're cheaper and more professional (not that I've ever met or talked to the chilicoke guy).
I'm sure there's more but these are the 3 guys I'd rather give my $$ to...