I got a load of fittings from a local pnuematics firm. Which probably doesn't help you.
The pic of the regulator you posted doesn't look like mine so you'll need to find out what outlet thread it has on it. My regulator also had a blocked off secondary port for a pressure gauge, which I got from the same place. Someone on Jim's reused one from an old footpump I believe.
Basically you should need to get the outlet of the regulator stepped up to a 3/8" beer line. 10mm fittings will be fine for that end.
Outlet on my regulator was 4mm.