Halfbacks are big money, given it cost Raiders 800k to get George Williams to play for them from the Super league I don't think it's really a question that with the new cap your looking at decent money to get him, plus he would need to be paid out of his contract.
Your 9th with Townsend but what can you honestly replace him with?
All the best teams have the good 7s, at this point the only way to get one is to experiment, you can have whatever in the other positions and without a good 7 your not going to be a team to challenge for the premiership atleast how the game is now.
That's the paradox your team is in, I would rate a team like Parramatta well above your roster at current.