Serialize JSON with invalid C# names

Hi all I have an existing Rest API I’m trying to use that has JSON like so
{ header-property1: "yo", header-property2: 42 }
Unfortunately trying to use JsonUtility requires that I name the field on the class the same as the property or key on the JSON side. Sadly C# does not support the - as a valid character in a name.

Does anyone know how to make this happen?

Could you do a find-and-replace to convert it to underscore, which C# does support?