Thank you.
It was the nut that was expensive over a fiver! So, I have ordered the bolt and will try to find a matching nut locally - to match the bolt that is! Also, the company you recommended was by far the cheapest including shipping.
So, again thank you.
I am from the age when the RD250 / 350 first came out when I was in my late teens. Everything was so much cheaper then. Some information I did get was that it was much cheaper to get a brake line from Hel (26 quid) against a replacement part (76 quid).
MrGee.