When you say that something is "good for the price", it means that it's better than other things that have a similar price, even though there are better ones that cost more.
In the same way, you can say that something is "___ for ___" whenever you want to compare something to other items in the same range. For example:
Sarah is tall for her age.
It was cheap for such a beautiful wedding.
You can also compare how well or badly someone does something:
You speak Korean well for an American.