Austin took his tally for the season to 14 after opening the scoring and then restoring Rangers' lead after Nahki Wells' equaliser.
The Sky Bet Championship promotion chasers, now second in the table, have been hugely reliant on their top scorer and want to sign at least one forward during this month's transfer window.
"That search is still continuing - that's all I can say at this stage," said Bond.
"Of course it's a concern. We haven't scored as many goals as we ought to for a side that's where we are in the table.
"You would become very vulnerable if anything happened to Charlie. It's there for all to see.
"We need people who can score goals and we need help in that department. We haven't finished teams off in the way we would have liked."
Huddersfield caused plenty of problems and missed excellent chances to score before Austin struck the opener after 55 minutes, firing home after Clint Hill's lofted ball forward had been flicked on by Niko Kranjcar and Andy Johnson.
Wells headed in Adam Hammill's cross to level up the scores in the 68th minute but Austin's header from Benoit Assou-Ekotto's corner gave Rangers the points.
Bond added: "We were better in the second half. We needed to up our game and we got two goals from Charlie, which has been pretty much par for the course.
"He's the one who has scored the goals for us and that's why we are where we are, as well as the fact that we've managed to keep the ball out of the net.
"I also thought Matt Phillips and Armand Traore made a difference when they came on as perhaps we lacked width."
Austin's goals meant the Terriers were left to count the cost of missed chances during a first-half spell in which they were the better team.
Huddersfield boss Mark Robins admitted the defeat was tough to take.
He said: "On the one hand we played really well but on the other we've not got that point, so it's difficult to swallow.
"In the first half I thought we were brilliant. That's no surprise to me, because we're good. We came here and took the game to them.
"We've done well, but we had clear-cut chances and should really have been 3-0 up at half- time. We didn't take those chances and you know they are then going to come at you in the second half.
"We conceded a poor goal from a defensive point of view and then they got the winner from a set-play after we had clawed our way back in with the goal from Nahki.
"To make that next step we've got to play like we did in the first half for the whole of the game. But I still thought we were good value for at least a point."