I picked up a partial project that's a '32 P&J Chassis with their IFS. You say that P&J told you the IFS is from TCI, but instead of going to TCI why not deal with Jason at P&J for your needs? They may very well make their own control arms, but regardless in my experience the guys at P&J will bend over backwards to get your problem fixed right, including swapping parts with you occasionally if it's stuff they still sell actively. If it's a P&J Chassis I'd say your path to getting it right is talking to Jason.