What Jage said is a good way to fix your swivel seat Sam. Another way, though probably not as good, is to get a large cresent wrench and adjust it down real small so it just fits on the vertical bent part. You then have a lever where you can (hopefully) bent it back straight. Then you can always hold a large chunk of steel (anvil, sledge hammer, etc.) on the bottom of the bent plate and whale away on the top with hammer. Not the best method, but it will work - depending on how straight it has to be. Ear plugs and gloves are not a bad idea here....
You can be anything you want on the Internet,
it amazes me that so many choose stupid....
2007 RB50, 6.0