Charlie Austin led the line in Tuesday evening's 2-2 draw at Leyton Orient but is one of just three recognised strikers at Loftus Road alongside Championship play-off hero Bobby Zamora and Loic Remy.
Redknapp has strengthened his defence with the signings of Rio Ferdinand from Manchester United and Steven Caulker from Cardiff and will now focus his attention on bringing in attacking players.
Redknapp told Sky Sports News: "We're just a little bit short at the moment and we need to strengthen the squad a little bit really. That's the problem.
"We've got two games in two nights and I've got Charlie as the only fit striker. We play tomorrow night at Southend and we haven't got anybody at the club who can play up front. It's ridiculous really.
"To be in this situation at this stage of the season, we really need to do something somewhere. We need to get Loic Remy back playing but he's not fit to play at the moment.
"We'll go to Southend and probably put a centre-half up front!"
OPR begin their Premier League season at home to Hull on August 16.