Replacing toilet to 3.5 inch copper soil

So yeah, changing out my grandparents bathroom. The old toilet was concreted to the floor, just to give you an idea of the state of it!!

Anyhow, the soil pipe is 3.5 inch copper, what adapter can I use to connect my toilet pan?

I have looked at the mkeb multi which is 3.5 inch but this just looks like a straight coupler and would be too small for the pan.

Any help is going to be great!!!

Thanks