Having had too many convertibles with rotted out seams, I was able to repair mine myself.
Go to a sewing store and buy a curved needle kit. May also be called a canvas sewing needle. Also get some heavy duty black canvas thread. Then, go home and start sewing! My top had about 6 ripped seams when I bought it and I sewed them all back together. When you're done, spread a little clear silicone on the inside of the repair job.
FWIW, I zipped the back window up the other night in the cold and my repair job held while the parts I hadn't repaired ripped.
Only costs a few bucks and an hour or two.