Ribeiro, who arrived in the summer following his release from Bristol City, was forced out of the weekend draw at Northampton due to a groin injury and is waiting to learn the full extent of the problem.
"I suspect he'll be alright for Friday (at Southend)," Laws told the club's official website.
"We'll keep our fingers crossed and hope he is, but if he isn't then we'll have to think about where we go from there.
"Do we slot Eddie (Nolan) back in at right-back and try and bring in someone else?
"I think we might have to look at bringing somebody else in on loan to see us through it with Michael Collins also out injured, but we'd be looking for a certain type of player for that."