I thought about getting them done locally, or just buying another set from Van. Let me know how your experiment works out.......and also when you get your new "bigger" ring :devioushey mate
why not recolour the ones you have.
dip them in weak caustic till they go black and then srcub them clean
hang them weak battery acid by a bit of wire and hook them to a battery with a bit of metal for an anode. when they stop fizzing dip them in some dye or blue ink.
I'm going to have a play with this process myself in the next week so I'll post some pics.