I tend to like genuine Tung oil for walnut. I've bought mine from Garrett Wade,
Lee Valley and Sutherland Welles over the years. In fact Sutherland Welles is
my go to. I think I originally found them at Garrett Wade 30+ years ago.
I use these finishes primarily for boxes. I have also used them on curly maple
with great success. (You can see some photos on my website at
https://www.mvr1.com/boxes.html . The early photos were with cheaper early gen
digital cameras but the later images are better.) I have used both the oils with
some driers and unprocessed Tung oil. When I have a lot of time I start with
the unprocessed sometimes thinned. I'll often rub it in with fine grit wet or
dry sandpaper. Then when it is dry I'll follow up with the higher gloss version
with some driers in it over the top. And then wax.