I have successfully done short-term repairs with one of those vinyl repair kits, using a piece of cloth as a backing (the kind of kit where the vinyl is heat-cured). Problem is, if it's a stressed area, it won't last. It's only good for barhopper seats and the like, that don't actually get used. Plus, if it's starting to deteriorate it's all over, not just one place. You'll be chasing problems until you finally replace it.
Get a cover from that guy in Canada who sells on fleabay (helpful, no?). A new cover for my LS cost me $50 shipped, looks like OEM, took very little skill to install.