It shouldn't be that expensive to pick up an Orange 5 frame. Build it up with a moderate spec should be comparative to any other decent alloy bike.
They get rave reviews, and although some think they look and are outdated, they really come under the banner of "it it works then don't change it". Ive had numerous Orange bikes, mainly Dh in the past and still rate them over all of the new designs we see these days. I currently ride a high end DW bike while although does well in some areas the Orange's don't.. it falls behind in others. And i still would consider going back to an Orange single pivot over it. And people that bag them i can guarantee have never properly ridden one.
Rick Boyer was distributing them in Aus. Give him a call I'm sure he'd help out.
www.orangebikes.com.au
OR
Unreal Cycles in the US usually do good closeout deals on year old frames I've noticed as well.