Maybe I can help to clarify some terms for Jeremy Lieberman, so that he can speed up his search for these old bits. In the 50s there were two major makers of frame tubes in the UK - Reynolds and Accles and Pollock. Reynolds used to supply quite a variety of different gauges of "531 DB" tubing, so it likely that they also supplied a variety of pencil-stays. I have a lot of British frames from that era and there is quite a range of types of these stays.. most of which are standard conical tapers, rather than biconical. It could be that the latter are not Reynolds. The slimmest stays that I have measure about 5/16" at the top end. I think that the stays will probably be plain gauge, but whether the other diameter stays are the same gauge is uncertain. Someone out there must surely have catalogue from that era. In the 70s and 80s Reynolds experimented with variable gauge stays when they went onto biconical ones..but had real problems.
The rapid taper chainstays are those described with a round-round-round taper. Surprisingly they were still used in the 70s. I have some on a 70s Carlton -by that time in Raleigh ownership, but whether Raleigh used old stock or had them drawn to order is uncertain. These could be obtained with domed-and-slotted ends or open ones. As for the Reynolds fork blades at that time they tended to be longer ie most brakes were 730mm and not 500mm. They also had much more curve on them, as the standard rake on most road bikes would be in the region of 2.5" to 2.75". The rake of the fork was also much more pronounced in a "hockey stick" style. Normally the tip of the fork was of quite a small diameter. The whole sweeping effect looked very elegant. We used to claim that we could see the "sweep" of the fork vibrating to absorb road shock. As for the Reynolds sloping crown I am uncertain about this. I recall most crowns being flat topped such as Wagner, Ekla, Dubois etc.. The only sloping crowns that I remember were the two-plate ones that builders such as Harry Rensch fabricated "in house". In France it was possible to buy these in. In the 30s Alcyon used to build their own semi-sloping fork crowns.. I don't think it was until the 60s that the full-sloping foged crowns such as the Milremo one was introduced. It still surprises how some of these old tube sets keep coming to light in the back rooms of older shops. unfortunately there are fewer and fewer of these open these days.
Norris Lockley... Settle Uk