Linseed is enough if you don't expect it to touch water.. could try danish oil, shellac from button lac, too.
Or linseed to give it a nice color and pop the grain, then clear coat.
Don't really need to thin the linseed oil, but mineral spirits should work, dunno if with BLO.. to make it easier to apply.
I just rub pure uncut tung oil with my bare fingers, dunno if that's bad ...