if you buy a brand new engine from vauxall does it come with a engine number on?

the reason i ask is i just pulled the head off a vectra and the engine is suprisingly mint inside ie no bore wear but has 190k on clock but were the engine number is stamped is just 00 00 00 00 so was thinking this has maybe had a new engine from vauxhall at some point as it used to be a fleet car aswell any a idea as i am curious