Ayuh...
Those are Spalted Maple from my firewood pile...I took them to 400 grit sandpaper, and then did maybe a half dozen coats of Boiled Linseed with 4/0 Steel Wool between coats...
Did them last Spring...Have also done some for Rugers and Smiths from White Ash, and Red Cedar...Took me about 3 sets to get the hang of it...
Thanks for the kind words...
ADDING:
If I can do it, anyone can...
The best piece of equipment I can recommend, is a spindle sander...