Full-back Omozusi and midfielder Chambers have failed to recover from the hamstring injuries which kept them out of last weekend's draw at Rochdale.
But striker Jonathan Tehoue hopes to be fit having also missed out at Spotland with a tight hamstring.
Midfielder Matt Sparrow picked up a knee injury during that game, but he has trained all week and will be available.
However, Tottenham loanee Paul-Jose Mpoku came on for Spring and could be handed a starting place.
The Os are currently two points clear of the drop zone having lost just once in their last seven matches.
Source: PA
Source: PA