That is an amazing amount of stored treasures in inventory for the project. It would be well worth having the sailrite on hand regardless of what a sail maker would charge to re stitch and modify your canvas. Worth its weight in gold to have onboard even if you have to get inventive to create a place to stow it below deck. There is a lot to be said for having the ability to make lasting repairs at sea instead of merely having to do emergency patching for your sheets or that of a stranded vessel you encounter. Anyone who has been at sea and survived a freak squall knows full well the value of spares and repair equipment
Good luck on your project. I'm just a land lubber but have been out there a few times.