Northern Ireland international David Healy is also available to Brown but after that he is without any more back-up.
After North End's fifth draw in seven games Brown said: "We are probably a striker short for the season.
"To survive a season with as many games as we've got, you need four strikers.
"We've three very good strikers in Healy, Cresswell and Fuller but if we get an injury to one we haven't got one for the bench.
"We probably need to look around and get another striker in. The transfer window's not closed for us, although there are players on the staff."