It varies, typically 4-8 weeks. I've seen it as quickly as 4 weeks and also have seen it at 12 weeks. I would suggest ordering from VivariumLand.com, they are based in Europe. Shipping will be fast and there won't be any 'funny' charges from the customs.
Thanks Marty. I did price things up there but it seemed more expensive. They also didn't stock the corner wedges for the Reptibreeze so thought it would be best ordering from MistKing directly.
Hopefully it's 4 weeks ;-)