'Adventure bike' Helmet?

[Fossil]

In the 'downunder' (Australia), we don't get much choice in 'adventure' style helmets, i.e. dirt-bike with a screen. Only one seemingly available is the Arai Tourex @ a much inflated asking price. Are there (trustworthy) mail-order businesses in Britain recommended for alternatives? And has anyone had good/bad experience with the brands?
Thanks in advance for feedback!... Fossil.