It's not like it used to be but an ambitious guy can make a living.
Urchins seem to be self renewing. They keep crawling up from the depths. They've been found as deep as 1200 feet. (Not by me.) Also the ones that are undersized today will be legal in 30 or 40 days. So you can go back to your favorite spots and get more. The Oregon divers tell me we get their urchin spawn cause the Japan current carries it down here to California.
SUBSURFACE PROGRESSION --Dive supplies , They can measure you for custom made wet suits there.
707-964-3793 ALBION RIVER CAMPGROUND
Commercial dock, ,protected little harbor, a favorite of local urchin divers.
707-937-0606