Does the EU now prohibit our photoshops from supplying Kodak E-6 fixers? If not Jessops supply the Ilford equivalent.
This website offers some tips on the subject:
Bamboo Rodmaking Tips - Tips Area - Hardware - Bluing
I think REC, who offer
Nickel Silver Ferrules, also supply blueing agents.
REC was imported by the same people that brought in Scott, who went under last year. WCB may know, as would Reneé at Foxons (St. Asaph).
From your post:
"If you get it too dark. Start over... the metal actually looks better after being re-stripped a couple of times.”
Can't go wrong really can you?

Good luck!