Unfortunately I couldn't find shallow speakers. Well, frankly speaking I didn't have the time to look for them. My speakers were all purring and buzzing whenever there was a bass tone. I took a closer look and it turned out that part of the speaker suspension unglued from the frame. Not the black rubbers on the membrane, but the orange material close to the magnet. So I glued this thing back and they sound like new. For now I don't have to look for speakers. Maybe if some of you are DIY guys, this could be a solution.
Ya, I put the sony speakers in the other day and they sound very nice. As far as doing the mod....I purchased a panel removal tool ($5), some wire connectors, rubber spacers, and foam weather strip. I put the foam on the back of the magnet and door panel to help prevent unwanted vibrations.