If you want more UV protection or just general protection than what the Surfix can offer,you can put an oil based Film Finish over the oil once it dries enough. I use Epifanes Varnishes if I'm doing this and have had great results, but you are probably okay with oil based finishes in general over the Surfix. Will this be outside? If so, I'd recommend Exterior Rated products only.
A water based finish might also work, but the Surfix would really need to be dry and not react with the topcoat.