Why don't you ask the vendor?

Can you just tell us the appliance?

They just got back to me and said they would send me the right plug for my US location.

UPDATE: They just told me it was a Canadian plug. Some google results told me US and Canada used the same plugs but apparently there are some differences.

Sous Vide cooker. Very small.

Canada uses NEMA plugs just like the U.S. so far as I know and we actually have a connected power grid. So I don't know how Canada's power would be different since it is actually connected to ours.

"CA" does not stand for Canada, it stands for "California". So-called California Standard plugs are 50 amp, 120 volt/250 volt twist-lock plugs as described here: https://www.mcmaster.com/products/california-standard-plugs/. The Sous Vide cooker you purchased may not be usable on a 120 volt, 15 or 20 amp residential circuit and just changing the cooker's plug will not make it so.

California Standard is CS not CA (sometimes Ca Std). I am not saying you are wrong in your assessment only that the nomenclature seems incorrect.

The link you have is for AC plugs which are plug locking (I thought CS were plug and body locking, but I could be wrong about that).

Is the plug UL listed.

UL is a testing lab supported by the insurance industry. There are some insurance underwriters who require UL for coverage.

People are using "CA" for California: https://www.amazon.com/dp/B004793C0U. (The OP may have purchased a high-wattage commercial appliance and be disappointed when he can't use it in his home.)