They already have the beam intensity in their specs: 75kcd (75000cd), which means "75000 lux @1m calculated", however kcd is the proper unit for that. (see here).
Really measuring @ 1m is a bad thing to do and calculating throw from that gives quite inaccurate results.
75kcd give 550m of NEMA throw, which is a somewhat optimistic value, half of that might be a more realistic/practical throw value - but that depends on the target you shine your light on.