Look, Eastern Bakery has a mooncake order form on the web now! But you still have to mail a check the old-fashioned way. I love it. They also have an oddly unlinked page explaining why theirs are superior to mooncakes from China.
I have this dilemma every year where I overenthusiastically buy a whole box of 4 mooncakes, & then like 2.5 of them end up going stale in the back of the fridge because the stuff is so dang rich—even if you invite friends over, everybody eats just a couple of slices. I guess a better tactic would be to go to the bakery itself & buy just 1 or 2, but that’s a bit of a slog for me, especially right now when it’s still hard for me to walk up & down hills. (Remember the pelvis? Well it’s the knee on the other side that hurts now, from all the compensating, aka weird moonwalking moves on one leg.)