Do I need custom blinds for my loft?

I live in a loft in San Francisco and am looking to replace the blinds in my apartment. The issue is that the main window is about 48in wide, but is 13 or 15ft tall. The ceiling is slanted with the roof, and the top edge of the window follows the ceiling, so the left side of the window is over 12in higher than the right side.

How do I go about getting blinds for this window? Will they need to be custom? And any idea of the cost range (I know it depends on quality of blinds)? Thanks!

Yes from the sound of it you will need to get customized and you should contact a local blind dealer in your area to get them made special fitting to your home.