Whenever I see an orphan size like that I think Metric - it looks like you might need a 4mm x .7 screw - if you have thread pitch gauges and set the .7 and 36tpi gauge next to each other they nest up nicely.
Have a look at these:
They show them 6mm long for a nickel a piece but they probably have a $50 minimum order or something :P
I like Jimmy's idea of tapping them for a more common size but be careful when doing so, especially when the same tap drill size is involved. Always try to be sure that the root diameter of your new size is at least the OD of the original fasteners. If the tap drills are the same size and the hole has been tapped (especially a "finer" thread), that material is already gone and there's precious material left to rethread.
Metric fasteners still give me a chuckle, as well as our American effort at metrication over the years. I always loved seeing a print with a 6mm x 12.7mm (1/2") fastener or a lot of 12.7mm and 25.4mm dimensions. And to this day when you go to the hardware you still see the screw diameter and pitch metric and the length in inches...
Oh, and I have no affiliation with Albany County Fasteners, they were just the first listing that appeared when I Googled "4mm .7"
On Friday, September 12, 2014 9:00:58 AM UTC-4, N. L. Devotie wrote:
I have the attached wheels on my car, and somehow I've managed to lose
one of the screws that holds on the center cap. Its actual a flat
headed allen wrench kind of screw. I'm told these are American Racing
Torque Thrust wheels, but some older vintage that was actually made in
Canada. I cannot confirm the accuracy of either of these two
statements. I've talked to some wheel gurus but got nowhere. I've managed to get an American Racing center cap screw
that looks identical to mine, but it turns out the threads are slightly
coarser. Any of you have these wheels and can confirm what they are?
Any source for the dang screws?