Rangers remain top of the table after Charlie Austin's penalty sank Yeovil on Saturday, but he is the only fit senior forward at Loftus Road following injuries to Andy Johnson and Bobby Zamora.
Redknapp has been keeping tabs on Tottenham youngster Harry Kane, but he came on as a substitute in their win over Cardiff on Sunday so the Rangers chief may have to look elsewhere.
"The problem I've got is that I only have one striker," said Redknapp.
"We didn't create a lot of chances, and without Charlie Austin we would be in trouble.
"We lost Andy Johnson and Bobby Zamora has had an operation, so it's something we are working hard to try and find somebody to come in."