Obviously, Eklund can answer that better than I, but I'd guess 100 is probably about what he used in this MOC, since he also mixed in some standard blue bits and some clear cheese slopes.
Keep in mind that 1x1's are usually pretty inexpensive though, so if you're going to order them from BL, it might be best to double or even triple the quantity, since a large percentage of the cost is going to be for shipping anyway
Congrats to Eklund on winning Garheim's LC1. There were a couple of others that we were considering, but the way you captured the feel of a boat tossing in rough seas helped to tip the scales in your favor. Nice job.