I think you might be interested in my latest update of my browser extension BrickHunter. With BrickHunter you can import a WantedList from BrickLink and check for prices and availability in Bricks & Pieces and Pick a Brick as well as automatically add the parts to the shopping cart in the LEGO Online Shop. With the latest update you can also create a parts list directly within BrickHunter by browsing the complete Bricks & Pieces catalog and then add it to the shopping cart. The parts catalog is always kept up to date. Sorting by price does not work correctly for all countries yet, because the indexing is not finished yet. This concerns the following countries: GB, HU, IE, NO, NZ, PL, PT, SE (in this order, per country it takes about 1.5 days).
The extension is available in the official Google Chrome Store for Google Chrome and the latest Microsoft Edge or in the offical Firefox addons (store) for Mozilla Firefox.
The extension itself is opensource: BrickTwo/BrickHunter (github.com)
A documentation is available for version 1.1 (current is 1.3) in german. I'm currently working on a update and will then also support english: Home ยท BrickTwo/BrickHunter Wiki (github.com)
Let me know if you a question or if are missing a feature.