Where are you based? You could contact whoever is the supplier for Gigabyte products in your country and ask them to give you a quote? Otherwise there are loads of online stores around who sell batteries for laptops. As for the restarts / shutdowns, hasn't happened to me. The only odd thing I've picked up with mine is some odd horizontal lines going across the screen near the Gigabyte logo when starting up. It's fine after that though. Your situation is really odd though. Was it perhaps dropped or damaged in any way?