Yes, it is a double fixed one.
Thanks, that makes sense. Thought I was missing one of the tabbed washers, but found them both on the other side! The side with the 'odd' cone, seems a mishmash of odd sized nuts / locknuts to try to match the spacing on the side with original parts. Would be nice to source matching parts, but good to know it'll only be for cosmetic purposes!
I was given a tip in another post regarding separating the alloy flanges from the steel barrel to rechrome it. http://www.retrobike.co.uk/forum/viewtopic.php?t=118082
Sounds like a fun experiment, but I'm unsure of my ability to be able to press them back together well enough should I get them apart. Ever done anything similar? I might just try to get matching lock nut and rebuild, see how they are.
Thanks again for the help Keith.