I was going to recommend Vistaprint because they are having their sales on wall calendars right now. I use them to print business cards and thank you cards and have been happy with them. The company I use for my art calendars (Gelato) is aimed toward sellers, but you could use it to buy products for yourself. It's a bit more advanced and you have to design the entire calendar. BUT the cost is quite a bit less than Vistaprint and they ship wolrdwide.
I'm a little confused by your questions regarding image borders. Is there a thing called a "bordered calendar"? Normally, and this is just my opinion, I would not recommend a border around digital images. But there are some nice designs on Vistaprint that have pretty borders (leaves, etc.). It's all personal preference, though.