Personal preference, I would think pine would get nicks and/or gouge marks after a while- I prefer hard maple but use what's available as long as it's clear pine and knot free.

Hardness is the main thing. When you push past the edge of the hide, youll nick and gouge the wood. Youll have so sand those a lot.

Wood Species Hardness
Hickory 1820
Locust 1700
Hard Maple ( Sugar) 1450
Coffee Bean 1390
White Oak 1360
Ash (White) 1320
Red Oak (Northern) 1290
Heart Pine 1225
Black Walnut 1010
Black Cherry 950
Paper Birch 910
Cedar 900
Southern Yellow Pine 870
Douglas Fir 660
Chestnut 540
Hemlock 500
White Pine 420
Basswood 410
Eastern White Pine 380

That's kinda what I was thinking. This is a plan that might work :

Get a pallet and cut one of the crossed boards to the size of the pipe. Then closer to the front(according to angle) put 2 2x4 side by side. The width between them should be the size of the pipe. Then put a crossbars so the pipe stays up.

(You might not be able to understand. Its kind of a rough draft))

Use a 2X6 cut out in the shape of a large fox board with edges curved. This size and shaped beam will accommodate all pelts larger than mink, marten, muskrat, etc which are easily fleshed on their own shaping boards using a small pelt (stirrup) fleshing tool. Also build it to fit your height angling up to your solar plexus. Made out of pine, fiber glassed to reduce/eliminate nicking and 30 years old:

My beam is made from white oak; bought it years ago. My son made his using a knot free, yellow pine 2x8 ... seems to work well for him with my old necker. I believe he used a coon board as a layout pattern.