The plaza is available on Amazon but at a higher price. £90 to £100. There’s also this. Expensive!
https://www.amazon.co.uk/Ferplast-Ka...s%2C116&sr=8-5
To be honest, if it’s for your neice I would get the Hamster Sky. I think it will be more manageable and allow more interaction and easier to set up safely. Even if it does cost almost the same as the Savic plaza. For example I have the Savic plaza and I also have the Savic Mickey 2XL (which is the same as the hamster heaven but mouse bar spacing) and it cost more than the Plaza! But sometimes it’s the right cage for a hamster. Our last Syrian preferred it to the Plaza.