The leftside plate should be OK. I would just check the feed cams to make sure they are not broken or damaged. If you post pics of your concern areas on the forum or PM for my email address we can better access your issues. You main concern with the casing (receiver) is to make sure the trunnion, bottom and top plates are not damaged. I have seen several display models were these parts were welded to the right side plate. These parts are available in newly manufactured form but are expensive. I see you are located PA which town? I am located in Southern New Jersey. You make also want to become a member of the 1919A4.com forum. Lots of expertise there as well plus vendors that specializes in the Browning MGs.
--fjruple