Hi
Have you tried R.D. Barratts, I have normally been successful in getting small tools inc BSB taps and dies. They are second hand tool merchants and cover just about everything from taps & dies (inc special threads) to measuring equipment. Normally reasonably priced. Telephone number
01422-205828.Normal disclaimer they are nothing to do with me or my co. no financial gain to me, not cynically trading etc. Anyone got one