The lugs on this frame look as though they could well be Brampton ones with the curious radius-ended "spearpoint" cut off. These were much in use around the late 40s and I recall having them on a Rotrax La Premiere frame from 1949'
It's an interesting point that Hilary raised about the lugged bottom bracket shell, and one that had not occurred to me. I have owned over the years about eight Baines..being down now to my last VS38..but only one of them had a lugless B/B shell. Can anyone out there give us a clue to when and why there were different B/B shells? My Baines catalogue from 1938 shows only lugged brackets..so perhaps the lugless type came in when bracket shells cast for the Baines vertical seat-tube became difficult to obtain. In the '38 brochure the frames were described as having 74 head and 72 seat angles... to customer's choice. With cast lugs being the standard type in those days that choice implies either some alteration of the standard lugs, or a wider range of lugs.
I have built a number of "Baines Gates"-type frames, and it was very easy to provide a longer top-tube without affecting the head angle...you just lengthen it at the seat-tube end. In a sense this would use the french type of seat angle measurement by measuring a distance set back from the vertical from the bracket, but I doubt whether Baines would use this method to offer his variety of seat-tube angles... not the same thing at all.
I know that at busy times ie when Baines' factory at Idle, Braford could not cope with the volume of orders for their frames - they made standard triangle frames as well - some of the work was sub-contracted out to Whitaker and Mapplebeck (later Pennine Cyles when the partnership broke up). it would be interesting to know whether the Pennine Baines frames carried any special suffixes or prefixes to their numbers.
As for suitable period-correct equipment for the "Whirlwind", riders at that time used a lot of UK-made accesssories such as Williams, Chater-Lea, British Hub Co, Blumfield, Bayliss-Wiley, BSA, Webb, Strata, Reynolds, Cyclo, Constrictor etc..but the more adventurous types would search out Durax or Duprat chainsets, Simplex or Super Champion gears, Lam or Gloria brakes, Prior or Exceltoo hubs. As for rims it would probably be Dunlop..or Fiamme..or Constrictor.
Hope this helps a little...but it just probably confuses you with the wide range of options.
Norris Lockley....believing that if you can't succeed in convincing folk, you should try to confuse them...Settle Uk