Check with our man Les Richters of Mainly Maico, and if he hasn't got them try the states - once you have converted to Aussie $$$ the UK option can often be quite expensive especially with their rather high postal charges.
http://www.vmxunlimited.com - try him first - he's Aussie and there for the enthusiast
http://www.eastcoastmaico.com - a great guy to deal with stocking Maico Only products and spares
http://rageracing.com - this site offers access to some good info including parts manuals
Cheers,
Dave Mac