As I said, #tartmode
Aside from the flashy paint and half-crome stays and fork, we have Chater-Lea cranks, Brampton B8 pedals, Brooks B17 Sprinter, the fashionable adjustable "Major Taylor" stem (although it was called an extension back then) and the then brand new Bayliss-Wiley Continental hubs. As projects go, it's obviously very nearly there. Works planned are a bit of clean up, new tape, brakes with less corrosion, fresh clips and straps and some tyres which (F) roll a bit better than a Wolber Invulnerable and (R) hold air. There should be some spare rings and sprockets somewhere to adjust the gear to something a bit more racy.
I've mostly been shopping brands which existed at the time, more or less. Parts acquired are:
Vittoria (est. 1953) Strada tubs. They're basically Rallyes with slightly different branding and seem to be exclusive to Decathlon. A solid "buy" recommendation at £14.99 each, even though that's 4p more than the frame cost 🙂
Christophe clips and straps (same manufacturer since 1922)
Velox (est. 1903) tub and bar tape
Fibrax (est. 1902) cables
Then we go a bit off piste with some some no-brand levers with suitable retro styling and the necessary ⅞" clamps and some Tektro R525 calipers because have you tried finding anything else in short-reach-nut-fixing-silver apart from maybe some NOS Weinmann 500s?