You might talk to a hydraulics shop about repair options for the existing line. I'm sure that bad section of the line could be cut out and replaced with a compression or flare fitting or even flexible hose. You would have to move the clamp a bit, but that might cheaper than replacing the entire line. Replacing the line is not difficult, but $50 plus shipping is not cheap. The fitting at the transmission is a banjo/hollow bolt arrangement. I would replace the seals on principle.
To make sure that this problem does not occur elsewhere, you can make some cushions for the clamps out of fuel hose.