Can I buy half a catty of pork in the supermarket?

Tell the fresh meat counter in that supermarket directly, and tell the chef there that you want to buy half a catty of meat and ask him to cut it for you.

Of course, because people's hands cut a piece of meat, there will be errors. After all, it is not a scale, and it is difficult to be so accurate. It's completely half a catty, or it may be a little more or less.