I've heard of people using hockey tape, heat shrink sleeve and overwrapping the overgrip, but I tried using a spare grip band underneath the overgrip and it created a decent flare... seems much easier to do, cleaner to reverse if you don't like, and replicate if you're doing this to multiple sticks.
If anyone is willing to give it a go, I know Tourna sells them separately and they come with a few replacement grips, along with coming stock on some racquets like babolat.
If anyone is willing to give it a go, I know Tourna sells them separately and they come with a few replacement grips, along with coming stock on some racquets like babolat.