B&M 10237 flexplate (big block Mopar, external balance), like new. $100.

Also have a Hughes 15LXTM neutral balance heavy duty lockup 'truck/towing' converter for Mopar automatic trans (had it in a 46RH). Has a single offset mounting pad.

Had to swap another engine in the truck which required a different flexplate, which has a 90* bolt pattern, which made it impossible for me to re-use this converter.

Has maybe 10 miles on it before the engine swap (sigh), so it's basically 'new'. $400.