Cost on a timing belt for a '03 sedona in Canada

Hey guys, I have an '03 Kia sedona ex with the 3.5l V-6 engine. It currently has 141 000 kilometers on it and I have never changed the timing belt. My thought process was "if it ain't broke, don't fix it" until I found out that it is an interference engine. Then the dealer told me that it would cost me between 1000-1500.00 to change it. I find this unbelieavable considering that this should be part of a regular maintenance schedule. Is there some one out there that has had this done for a much less canadian dollar amount. Or is this a relatively easy change-over for a guy that has some mechanical knowledge and a bit of spare time on his hands. Thanks Lance