Can a mirror that is already framed be resized?

I have a large master bath that needs mirrors on all three walls. I found a large framed mirror that I really like that will fit well on the two large walls. I'd like to purchase another, though, and have it resized to fit the remaining small wall. I'm wondering if it is possible to pay to have someone recut the mirror and frame to the size needed. The height is fine; I just need the length changed.