Stop repeating yourself! Dia-Compe AD990. I hope you're ok with a black one, if you want silver I have to dismantle it off the Hwa Fong. How long is the steerer? I may have 1" threaded, but weren't Pioneers quite high at the front?
Oooh, that's a beautiful frame... Straight bars & barends would imho estethically fit better though, but if it's for commuting, do what is right for you...
You can also fit Magura Hydrailic rim brakes, requires a wee bit of fettling but members of this site have done it, think the mounts have to go on upside down or something :?
Pete, you will have to get an ENO to avoid offending people! The most age related fork I have has a whopping 200mm steerer, brazed crown & includes big old Dia-Compe Cantis, or how about a Specialized unicrown, 147mm steerer? not sure how far down the threads go, both are still in frames. You riding tomorrow? I can bring the brake along.