Search for railway chairs to secure sleepers

From: "Andrew Johnson" andrewtasmanjohnson@msn.com

I want to obtain several metal railway chairs used to secure metal railways on their wood sleepers. Of special interest would be those invented by James Walker (of Slaithwaite, Yorks and Warrington, Lancashire) and probably made by his Chandos Iron Foundry in Warrington, Lancashire around 1860-1890. The reason is that this James Walker is my ancestral relative. He worked on the Huddersfield and Manchester Railway and Canal Company and on the London and Northwestern Railway Company.

Would you please point the way for me to obtain some of these railway chairs?

—Andrew T. Johnson