It looks like a good idea.
Seems that in a quantity of a thousand, the cost is $2.94 each. Of course, that drops to 81 cents each if you get 10,000.
Of course, the big calenders are $5.50, but discount is available if the order's over 5k it says. $1.51 each at 10k quantity.
To be honest, I think that you'd be well off to see if you could get the calenders into the bookstores. Might be a bit late for that though.
Too bad calenders get dated so quickly. Otherwise, it ends up being like the advice I give to some of the aspiring musicians I work with: If you can sell a CD for $5, you can make money getting them professionally printed, complete with Jewel case and insert, giving you $4 profit each. Just throw a display up at the places you perform at.
Why $5? People will put down $5 a whole lot quicker than $20. Of course, trying different price points always helps. You sell 5 of them a night, that's $20 more for the night.