Jack,
I proposed such a double wedge device a couple years back here, but I never made one. It should be more versatile than the hydraulic type IMO, since you could beat heck out of it with no problems and it'd have a larger anvil area. It'd be a bit of work, obviously I've gone the easy way and made individual plugs to do each job as I go. It takes about 15-20 mins to make a custom plug, start to finish for me.