Flex Plate for 360 Magnum Engine

OK trying this again I have a Hughes Neutral balance ( No weights ) converter. I need a flex plate with the weights so I can make this work. 360 Magnum with 727 transmission. Where can I get a flex plate that would work? I don't remember if the stock flex plate had the weights or not ( which I don't have ) or is these an aftermarket plate?

Thank you for any help.