Honda-SOHC

Tool kit is almost all there.. The spark plug spanner is original, bit battered but better than you can buy new these days. You're missing the flat bladed screwdriver and it's handle, the spanner isn't original, there should be a 10x12mm spanner and a 14x17mm spanner IIRC, the C spanner also doesn't look right. Does the box spanner fit the rear wheel nut? it's a 26mm one and for some reason I suspect it should be 27mm, the 500 used 26mm so it could be the same.

So long as the faces of the letters are ok, no scratches, flaking etc then just touch up the outside with some Humbrol Satin Black No58 paint Phil.

If the faces are really bad, consider trying to restore them using chrome spray or gold if they were originally gold.

Pilot lights can’t be seen as definitive though Graham, if it is an import then the first thing the dealer needs to do is convert what isn’t standard on the bike to UK spec, as the headlights of those days were handed beam wise they’d change the headlight for one dipping the correct way, change the headlight and you change the pilot light. I agree that the parts book has some errors but not in the country designations for certain parts, only the USA got a different right hand switch as it has extra functions that the rest of the world didn’t need.
From the carb numbers it’s not a German or Dutch model, it could be French or European Direct Sales. What’s interesting is that if you study the frame in the parts book certain countries got different frames, maybe they had an additional bracket or something but what that difference is has never been listed, could it be the VIN plate for instance, UK and certain other countries didn’t get that feature but we all know the USA did.
If I had to guess I’d say logic dictates importing from the closest country if you couldn’t source one in the UK, in that case France is favourite, what makes me wonder though is why if Honda didn’t send any to the UK officially why are numbers allocated to the UK market? It could be as simple as Honda Japan making them to UK spec but HondaUK deciding for some reason not to import them, which makes you wonder why they’d do that. In line 4 cylinder bikes were in demand, the 500 was a new model, only the second 4 cylinder that Honda made so interest in them would have been high, it was also significantly cheaper than the 750, so again a strong selling point yet Honda decided not to import them until the K1 came out. Pressure from the UK government to try and protect the British bike manufacturers? something we haven’t factored in like a dock strike making importing hard?
It could be something as simple as Honda diverting bikes to Europe intended initially for the UK and dealers encouraged to go and import a few in the backs of vans. 

I saw it as well Andy, ace bars were the first pic and then a couple of other pics of normal bars. Seems to have vanished, check your browser history in case it’s been deleted

Could be 550f2 or 750f2, only by measuring the distance from top of the bottom collar to the top can you tell. First dibs if you’re selling them please if they are 550 ones

If the locating peg holes aren't there let me know and I'll measure my bars and advise as they are off at the present.

Standard on UK models Phil, USA didn't get it though, just a horn button for them.

Looking at the pics it looks like it might be an expensive restoration if all the chrome doesn't clean up well. Certainly very dirty, lets hope it's ok under the muck.

All the US bikes had a vin plate up front. I only see the Made in Japan, so that would make it almost certainly Europe. Anyone know why Europe got K0s, but UK got next to none.

Could be something as simple as supply. Maybe Honda knew it couldn't supply both Europe and the USA as well as the UK. As the smallest market would have been the UK we were left out. As it turns out that wasn't to our detriment as the K0 had quite a few problems that have been well documented. The seat lock was a step backwards, the K1 lock is far superior. The reflectors are better bigger as well. Not to mention the switchgear which was slated so much by the press that Honda had to change it for safety reasons. The only thing that the K0 got right IMO was the gold colour, Starlight Gold is nicer IMO than the Candy Gold custom of the K1. No idea why they changed that, maybe they thought it looked better with bigger metallic flakes. What I'd like to know is who made the decision not to import the Candy Jade Green model, far better than the awful brown model, again my opinion.