Thanks so much for the replies. I knew I'd come to the right place!
Foreigner
Thanks for the info. No, sadly, I don't have the forks. I've got a nice chrome pair I'm planning on using instead.
And that's a beautiful bike - you've clearly put a lot of work into her.
Johnny69
Good to know it's the right age. That, coupled with the serial no format is reassuring.
juvela
Wow, that's quite an endorsement! By spooky coincidence, my only other vintage bike is also a Bob Jackson Merlin!
Thanks again all. I'll be back to let you know how it turns out.