With all due respect, only the uranium nitrate is not readily available from UK from photographic suppliers, as Chamaeleo pointed out in the first reply to my OP.

Many of the others mentioned in this thread are in the formulae for commercial photographic products, and Ferricyanide is often named in APUG threads as a component of bleaches.

In the process of not writing it off the experience, on this occasion, I am actually gaining experience and knowledge.

Consider - How did you gain your (considerable, judging by your work and publications) knowledge and experience?