Buy a cheap one and modify it. This is the safest & most cost effective way to do this.
Are you wanting a copper or stainless steel one?
You can buy anodized aluminum “laminate” in any metal finish you want,
that is bonded to a phenolic baking for a fraction of real copper or stainless.
It is not malleable, it is made to contact cement onto any clean surface.
Let me know if this is what you’re thinking of.