Posted this on the off chance that someone might have a rear swing arm for an Orange 5 that they want to off load for a suitable sum. It's the very first year of the curved front on the arm (as opposed to the old style box shape) - the bike was bought late 2006, but I believe it was the 2007 frame. Although a later version might also fit.
Even better if it's the dark grey/charcoal colour !!