Clarification on size of Beast of Nurgle model (not base) for proxy purchase

I'm not a huge fan of the GW look for the Beast of Nurgle, but I want to add these little tanks to my roster. I want these guys as a proxy, but I can only find them being sold by model size, not base. They are selling at 28mm and 38mm from here. Is that model going to be the right size when put on a 60 mm base? I don't want to purchase them and have someone accuse me of proxying for advantage.

https://preview.redd.it/bqwkt70zk55h1.jpg?width=1588&format=pjpg&auto=webp&s=26fc1ead5e365692132b54c2e3ca57cc8b5bcb3c