Do you have oddball sized duct openings?
The Pickford style custom grilles can be made in just about any dimension you might need. Made from hefty 1/8 inch thick solid copper, brass, or stainless steel. Suitable for wall or ceiling use, but not for floor unless you are thinking about something very small such as a shower floor drain.
Typically, customers want the option that involves a brushed finish followed by a clearcoat. However, sometimes people want to do that themselves or maybe don't even want that at all. That is fine, but just know that in an unbrushed state the metal has a lot of unsightly scratches that if left alone are probably objectionable.
Sorry, dampers are not available in Pickford grilles. However, if that is absolutely necessary you could probably find a local HVAC person that could attach a damper a fraction of an inch back in the duct.