Several years ago I considered a Toppeak handlebar bag. I do not recall why I chose to buy something else. But their price is closer to what you want. If you see any in local stores, give them a look.

A good handlebar bag has a quick release system that allows you to detach it in seconds and take into a store or restaurant with you, when touring that is where my valuables are. But much weight in them can impair bike handling a bit, that is something I got used to quickly.

I bought a Louis Garneau bag several years ago, they no longer make them. The box stiffeners were quite weak and it badly sagged. I eventually had to reinforce it with two aluminum bars that I cut and drilled for the purpose, if they were still making them I would not recommend that one. My point is that a cheaper one is less likely to have adequate structure.

I have a waterproof cover for mine. You should think about what you will do if you are caught in a downpour.