Nice job, Mark. I had a tough time finding good beef ribs in local stores too. Hapenned to stop by a local meat market/smokehouse/BBQ joint. Noticed they had smoked beef ribs. Asked if they would sell me some raw ones, and ended up buying a slab. They cut it in half, so I ended up with two rows of meaty ribs about 3" long and 2" thick.
I usually braise them low and slow in the oven for 3-4 hours. They are great, but will try yours in the smoker next time.
By the way, great looking ABT's I will gleeully steal that reciepe when I make some tomorrow night!