Try taking a look at the link, fishbulb.
So it's a posh little greenhouse? Or a dry fish tank?
Whilst I think this is the cheapest I have seen online, if you are near Sussex try Purple Pets near East Grinstead I got the same Exo Terra above for a Mossy Gecko for £179.50, yes £179.50. Also all Exo Terra vivs are cheaper with 45*45*60 costing about £60. I know it's not online but for those sort of prices you could justify a fairly long drive. They pride themselves on being pretty much the cheapest anywhere in the UK.