Yeah, that's the classic Amazon cube experience. The £40 vs $40 thing is mostly exchange rate plus UK VAT, so that part isn't necessarily a rip-off — but the bigger issue is that on Amazon you're often buying from a random third-party seller, or from commingled warehouse stock, so you can end up with old stock, a returned cube, or one that's been knocked around in storage.
Dedicated cube stores are just better for this: they actually check the cube before it ships, and if something arrives broken they'll sort it out. Since you're in the UK, KewbzUK is the obvious one — they'll usually work out cheaper than Amazon once you factor in that you're getting a properly checked cube with real support behind it.
If you do ever buy on Amazon again, check the seller name is the actual brand or a known cube store, not a random marketplace seller — and if the price looks way off compared to the cube stores, that's usually a sign something's up.