This belt sold on eBay has the same mark
http://www.worthpoint.com/worthopedia/vintage-nurses-belt-buckle-marked-424959506
as does this buckle VINTAGE-EPNS-SILVER-ENGRAVED-NURSES-039-BELT-CLIP-BUCKLE-EXC-CONDITION item 131363481693 ended eBay item.
Obviously a common enough manufacturer of these EPNS belts.
I'm not sure why you know it is a Scottish nurses belt? We can't see it - I assume the thistle design? As far as I know, nurses only wore the 2 part buckles. As a fashion accessory they are commonly known today as nurses belts - the links usually reflect the design of the buckle and are joined by simple rings or hooks. I would think their heyday was 1890-1920? I suppose anything and everything could be reproduced these days but frankly I couldn't see why - they are not worth enough. (Sterling silver would be a different matter of course). Anyway you should be able to tell by the surface wear - yours certainly looks old. And the weight - these are usually quite heavy. As a complete belt they are seldom long enough to go around modern waists. However they do sell - it is a long time since I had a complete one - the hoped-for value would depend on how ornate the design was, the size (width of the links - those with larger more ornate feature links at the front often are most popular), length for wearablity, and most important, condition - often the silverplate can be very worn.
