Do you want it white or just blonde?
Also, where are you? It might affect suggestions of products π
It doesn't look cheap, but there's a few ways to tone it. Are you at all worried if it goes on the slightly lilac side? I would start by getting a silver shampoo. I like bonacure silver shampoo which I get on Amazon, but touch of silver which you can get in boots and some supermarkets etc is ok.