Um, the big print houses probably run these things on the stuff I turn a wrench on
Most
good full service, print shops can compile your artwork/files and plug it into any number of graphic programs and print one of these, including folding and saddle stitch, in a few minutes. This would be on on 80 or 100 pound gloss text on 11x17 or 12x18. The holidays come pre loaded and you can add your own "special" dates - the day Uwe bought his 500th bass or whatever. This could be fun.
One of my best customers can do this though I have no idea on price. There is some amount of setup charge to build the job up in, most likely, Adobe InDesign. They will not be the cheapest, i.e Vistaprint, but I can vouch for the quality of their work and, ahem, I can vouch for the quality of the output
They will be reasonable especially considering the finished product.
If there is interest I'm happy to help with this as this is in my sphere of professional expertise - I just would beg off of total ownership of this - I have way too much on plate right now. I just can't see myself addressing and mailing off 100 + individual calendars right now.