It is quite possible that he had served in the regular forces (although not with the 36th Foot (Herefordshire regiment) who had seen no active service since the Peninsular War), probably in the Crimea, subsequent to discharge, as many did, joined his local volunteer force, and presumably attached a similar suspension so he could wear it with his official award. The regulations for wearing medals were much more haphazard than later as can be seen from many photos of soldiers from this period. As for the hallmark on the medal, presumably NRA had some old stock lying around which nobody apart from a silver specialist was going to give a damn about receiving. Medal collectors should always remember that medals were adapted for the recipient not for the benefit of collectors.
Paul