All indications are that except for footage that was retained for GAMBLE, there is no known footage surviving from RINGSIDE. If there was, Fox would have included it on the GAMBLE DVD as an extra.
Of course it is possible that some footage is still in the Fox vaults and they're not aware of it, but I wouldn't hold my breath. Since the film was scrapped there would have been no reason for Fox to hang to the footage afterwards.
