I use neoprene fingerless gloves in winter, but have now started wearing a golf glove on my left hand. This is mainly for helping to grab slimy fish , and preventing getting spiked, but would also stop blisters and prevent sun damage.
They are skin tight, so you dont even know you are wearing them, and they also help give you a bit of added grip on the paddle. any golf shop or sporting section of chain stores should sell them
pic attached