When I played Pebble a couple years ago, they allowed 48 hour advance booking for non-resort guests on the course. I had no problem at all calling and making a tee time for a Saturday in June. I had a buddy who walked on to the course in a foursome on a Friday afternoon last August and went right out. I know at least a dozen guys who have played the course without staying in the lodge, none of whom had any trouble getting a spot.
Now, I get that you're planning a trip and may not be comfortable leaving it until 48 hours beforehand to book. You certainly won't get your choice of tee times if you wait until that late in the game. But with several hundred dollars of potential savings, I'd be remiss if I didn't mention that booking isn't nearly as difficult as you might think, provided that you're willing to accept a tee time in the late morning or early afternoon. Then again, the advantages of a preferred tee time at Pebble are better than at most courses, as it can be the difference between a 36 hole day that includes one of the other outstanding nearby options and a 6 1/2 hour round.