Nuneaton born Hildreth, who came through the City ranks, has been released by the club and is looking for a new employer.
Hildreth (4) on the ball
The midfielder,who played for City Reserves against Bradford City on Monday afternoon, has also had a trial at Oldham Athletic.
The game which could lift Vale to second in the table will see Hildreth on the same side as Conor McCormack. The defender has been released by Manchester United but appeared for Bradford on Monday against the Sky Blues.