Walker serves a one-match ban after being sent off for turning a shot away from the goal line using a hand during Saturday's 2-0 loss at Hartlepool.
Should manager Alan Knill name his strongest team then Robbie Gibbons would likely come in to replace him.
Paul Reid (hand), Callum Kennedy (toe), Damien Mozika (ankle) and Michael Collins (tendonitis) remain ruled out through injury, though Reid is due to have the cast taken off his right hand on Wednesday.
Should Knill opt to give fringe players a chance, then Connor Jennings Mark Hughes, Jordan Keegan, James Severn and Callum Howe could all find themselves elevated into the starting XI.
Yoann Arquin comes back into the reckoning for County, having missed their last three games through suspensions.
Defender Carl Regan, midfielders Gavin Mahon, Hamza Bencherif and Joss Labadie and striker Enoch Showunmi join Arquin as potential starters should Keith Curle, the Magpies boss, opt to rotate his squad.
Teenager Romello Nangle was included on the bench against Bury at the weekend and the 17-year-old could be among the substitutes once more.
Source: FOOTYMAD
