A blob of clear lacquer from a touch in kit should seal it up.
Make sure the area is completely clean and dry before applying the lacquer so you get good adhesion of the lacquer to the damaged area.
If it was me, I'd attend to it sooner rather than later; if it's left as it is, there's a risk of white worm corrosion setting in if water gets under the damaged lacquered surface. You could then be looking at a wheel refurb costing around £80 or more.