For contacting Brightspark you could try ken@brightsparkmagnetos.com or send personal messages through the forum to members KenF and Groily.
When I needed my K2f magnetized I phoned-up a local magnet supplier and got them interested in helping out with a vintage motorcycle. We worked our way through three different magnetizers before getting it right and my host stood by while I did the field-strength test using compass deflection as described here in the forum.
Richard L.