I've obtained grease fittings for vintage British bike head tubes and bottom brackets from British Tools & Fasteners
http://www.britishfasteners.com/
Look under "grease nipples,"... you want the 2BA thread ones.
Now that we're talkin' 2BA, if you need 2BA bolts for the dropout eyelets of your British bike to mount mudguards, you can find them on eBay. Search eBay Worldwide for "2BA bolt" or "2BA screws" [e.g. # 280191485236 ]. Don't tap out those dropout eyelets to something else; use the real thing. Keep the 2BA flame alive.
Peter
============================================
Peter Brueggeman
La Jolla California USA
pbrueggeman(AT)ucsd.edu