Parkinson made eight changes to his starting line-up for the Carling Cup clash at Shrewsbury on Tuesday night and watched in dismay as they threw away a three-goal lead to lose 4-3.
Rob Elliot will reclaim his place in goal from Ross Worner against the O's while veteran duo Christian Dailly and Gary Doherty should be restored to the centre of defence.
Midfielder Alan McCormack, winger Kyel Reid and striker Akpo Sodje are also in line for recalls.
Therry Racon should continue in midfield as Jose Semedo serves the second game of his three-match ban.
Left-back Kelly Youga (knee) remains the only injury absentee.