Thanks for your question to the forum.
I assume you are talking about a meat pie??
The Information from the Traffic Light Guide Carbohydrate Counter tells us that an average individual meat pie has 34g of carbohydrate which is equal to 2 carbohydrate exchanges. An average party pie on the otherhand has 8g carbohydrate which is equal to 1/2 a carbohydrate exchange. So it really depends on the size (and type) of pie you are planning to eat.
I hope this helps to answer your question? You may find that a book like The Traffic Light Carbohydrate Counter is a useful resource to look up the carbohydrate exchanges in all sorts of different foods. Otherwise your dietitian may be able to provide you with an exchange list to have at home.
For more information about exchanges, talk to your dietitian next time you are at clinic.