On-loan striker Porter and winger Taylor both missed last weekend's disappointing 3-1 defeat at Walsall due to respective hamstring and groin injuries.
But boss Graham Turner will be keen to see the pair return against the O's as Town chase the first of four wins he believes will be enough to secure League One survival.
On-loan defender Rob Edwards is definitely missing, though, having this week been ruled out for up to a month with a quad muscle injury.
Defender Jermaine Grandison managed 45 minutes for the reserves in midweek following his lengthy recovery from a hip injury and will hope to be back in the fold at Crewe next weekend, while midfielder Mark Wright (knee) is a couple of weeks away.
Forward Luke Rodgers found the net for the second successive week for the Under-21 side, strengthening his claims for a starting berth.