Renting columns

I have to decorate my ceremony space on my own, and I've gotten the aisle done (in my mind). I think 2 40' columns at the altar with two of my centerpieces on each one would be lovely.

So here's my question: where would I be able to rent these columns? And not cost an arm and a leg? Has anyone done something like this before?

Thanks for the info! I've decided to scrap the columns, and I found a simple canopy that will work very nice :)

I love my LIW ladies. You guys are the best!