I think "trade names" will always bring somewhat less than the known name. Did you read the piece on E.C. Hodges? The English used the same action for lots of guns but you will pay a higher price for a Westly Richards or a Purdy than an Army Navy or a Charles Boswell but in many cases the actions are from the same maker. I have a 16ga back action hammergun from J. Venables & son, a friend has a 20ga hammergun from William Ford and the actions are identical and look the same as what I have seen on a Purdy and a Boss.
I saw a nice Stephen Grant side lever hammer gun on another site that was actually actioned by E.C. Hodges but as its a 12 bore (not a big fan of the 12) and its nearly 10K I'll let her slide on by....now if it was a 16 or a 20 that would be a different story