Air Filter Screw

Hi Everybody,

After doing the Dieselgate fix I wanted to try something to get back the car's driving characteristics.  I have a K&N high flow air filter.  When trying to do the install I lost one of the screws and was given a place holder.  I want to have a more authentic looking screw in there when I do my 90k check up in a few months.  What screw can I use to replace this missing screw?

BTW-
Driving wise the car is doing much better, the fuel economy drop from the fix has been recovered.  The Swedes checked the Dieselgate fixes and showed that the 1.6 TDI gave the 90 hp engine closer to 105 hp, but a shifted power curve.  The air filter has probably upped me to around 115 hp, though I can't confirm this without a dynometer.