Leading scorer Tomlin missed the weekend victory over Oxford after sustaining a thigh problem in training on Friday and is scheduled for a scan on Tuesday to assess the damage.
Laird misses the game against his former club as his late substitute appearance for Orient in round two means he is cup-tied.
And fellow midfielder Spillane is also ineligible after scoring for Dagenham in their win against Stevenage earlier in the competition.
Ryan Leonard could come into the side after he came off the bench to score the winner against Oxford - his first goal since August 2011 - while on-loan midfielder Ben Reeves could be handed his full debut.
- Sports & Recreation