I'd go for it, Stafford is putting up great numbers and has Megatron to help him out. And if you are going to include Austin in the Deal that might help out his/hers weak WR position. I don't think you even need to include Murray.
The only thing is I'm not sure how deep you are at WR. Giving up 2 really good players for 1 great one is not always your best move. Stafford's and Romo's scores should compare to that of Drew's on average but with someone other than Austin in your WR slot you might end up actually scoring less than you would with Stafford there.