1. Some issues with the word produced:
On the majority of items is written a label: Made in XXX (e.g. Made in China). I know the word: производить and I suppose the existence of the word производиться. So I would written: "производится в Китае" or "произведён(-ный) в Китае" . I also found "сборка производится" which if I am correct means: assembly takes place. I also found the word: собирается which might mean the same but I don't know.

2. Also I don't understand the meaning of the following sentence:Кольцо выпускается трех размеров

3. How is the word subtract and become in russian. For example I want to say: "If from the price I subtract the discount the total price will become one thousand euro"

4. I wanted to ask a client interested in a watch with a leather strap: "Do you afraid the the leather strap would be destroyed". My employee told me to say: Вас беспокоит кожа быстро приходит в негодность? but I cannot understand the phrase приходит в негодность. I wanted to say: Вы боитесь что кожа разрушается легко.