Having just spent many hours and a bunch of fibreglass making a 'cheap' bodykit fit my VS, the first thing I would do is scrap that 'cheap' requirement. You get what you pay for.
The kit I bought looks great, a copy of a VX R8 made to fit a VS. Hit a roo with it though, and discovered that most of the internal fibreglass mat is completely dry.. no resin on it at all !! The fit was terrible, I have had to add bits and remove bits to make it fit, and given the back of it about an extra 3 kilos of fibreglass just to reinforce it coz it was so weak. The fog lights I paid extra for were GLUED in, unwired, and of course fell out when I hit the roo.
The end result is nice though (check my album), just be prepared to put in the hard yakka.
I bought my Monaro bonnet from Savage Fibreglass in Bargo (Sydney).. he says he can source pretty much anything at the quality he makes, which was nothing short of superb. I'd recommend them without hesitation. Remember though, you pay for quality. His quality Monaro bonnet was $650, the entire el cheapo VXR8 kit (front and rear bars, and skirts) was also $650.... Savage can also supply stuff in steel or steel/glass combos.
Beware also of anyone that wants to fit the body kit 'while its still fresh and pliable, to get a better fit'. If its well made, it will fit without going through this B.S. If they need to 'adjust' it then its a crap kit...
All that said, I couldn't find a quality kit with the look I wanted, so I bought the cheapo knowing I was up for some hard yakka. If you are willing to do that, it opens your options up considerably. The cheap kit came from XXX Bodykits in Dandenong (Melbourne). Both of these companies do stuff for VT's too of course.