[Closed] Replacement/extra Lenses for Smith Goggles - where from?

Anyone know a cheap place to buy extra lenses for Smith goggles?

(for snowboarding in my case, but I figure some folk on here may use them for DHing etc so worth a punt)

I've got the [i]Blue Sensor Mirror[/i] lens in mine, which are great in flat light but can be a bit tiring on the eyes when it is sunny out (70% light transmission will do that) so I'm thinking an [i]Ignitor[/i] lens (35% VLT) might be useful.

But the only place I can find in the UK selling these is [url= http://store.prolens.com/smith-prophecy--prodigy-replacement-lenses-p529.aspx ]RxSport and they want £50 for it[/url]! 😯

The same lens in the States can be had for ~$40 USD.