One of the best I have used is by General, Armorseal.It is stricly wipe on,a urethane varnish with tung oil
I have also used Min Wax Helmsman Spar Varnish with urethane.
I use it uncut for the first few coats to fill the pores( no wiping).Sanding down with 320 paper.I then cut it with about 20% tung oil and start putting it on with a brush and wiping it dry. It takes some experimenting to get the final coats the way you like them and smooth, and sometimes you need to sand with400, 600 and 1500 wet paper after dry. Then set it aside for a month to harden and then buff out with rottenstone to the luster you want.
With a little practice you can get an oil finish look, but more durable
