I don't think that's correct. If the answer is "one", the thing asked for should be countable, so "how many" should be used.
E.g. How much money? - One dollar (it's OK to use "much" and "one" because we have "dollar" here).
How many [dollars]? - One [dollar]. (The word "one" is counting something, as well as the word "many", cannot use "much")
I'm not sure though, I'm not a native speaker of English :)
Wouldn't 'how many' be more logical here? If I ask for a price I would not expect an answer of one.
I'm guessing you would want to use "how many" when referring to multiple items, and "how much" when referring to price, but in Ukrainian it's the same word so you shouldn't really worry about it too much.