Meat Basher

I need something that I can use to flatten escalopes instead of banging them with a rolling pin. At the Selfridges meat counter, rather than a mallet/tenderiser they have a great big heavy flat plastic basher which covers the whole chicken in one bash. If you can't find something like that, then a more usual mallet like the one in the pic would be great, but I'd really love something heavy and much bigger/flatter.