*not a teacher
"pocket money" is the saying, not "money pocket", but you would not hear it used in your example sentence.
You have or use pocket money (money in your pocket), but things don't fit your pocket money.
In the United States you would likely hear "pocketbook" instead, which might be the word you are looking for. A pocketbook is a handbag or purse.
You might hear instead
"She only eats at restaurants that fit her budget"
"She only eats at restaurants that fit her income"
"She only eats at restaurants that fit her pocketbook"
The salary one would be understood, but not commonly used. You would probably hear the word income instead.