"...222 Jet..." That'd be a .22 Remington Jet. It's a necked down .357 case and uses either a .222" or .223", 40 or 45 grain bullet. A S&W Model 53 revolver used it.
Ammo and brass isn't being made by any major manufacturer. However, OWS lists 50 rounds at $49.95US(that's cheap. Buffalo Arms wants $76US per 50). Epp's is OWS' Canadian distributor.
Prvi Partizan is apparently making brass too. May not be available up here though.