Look on eBay ... ( Action wrench ) ... Although my first action wrench was made from a 4x4 piece of oak ... I shaped it to fit ... Then cut a slot so it would compress and put it in a big vice .. it worked held very tight ... Since then I have got others on eBay .. berrel vice is the hard one ... My first one was made from oak with with some big pieces of aluminum and bolts for a clamp .. I posted pictures here on this sight ... I have seen Krag barrel wrenches on eBay before although not very often ... By far the hard one was a barrel vice ... Remember to use lots of rosin to make it hold tight ... Good luck ....