JOEL - I really am not an authority on the pouch mail system. It was my understanding that only letters could be sent and nothing else. You might want to contact DearElder.com or the MTC website and ask them about this, and let me know what you find out.
LINDA - I did some research and found the following from my son's Mission "packet", which I am including as an FYI.
"Because of the uncertainty of mail delivery in the country to which
you have been called, the Church provides a "Pouch" service for letters
from family and friends. Please follow these instructions on how to use this
service. Letters received on Friday will be included in the next pouch.
Please be certain to put the full name and return address on all
letters.
Mail that cannot be sent and cannot be returned will be discarded.
IMPORTANT: Only letters may be sent in the pouch.The Church certifies
to customs officials that "pouch mail" contains documents only. Therefore,
this mail cannot contain currency, personal or traveler's checks, stamps,
credit or debit cards, phone cards, food products, prescription or
non-prescription drugs, merchandise of any kind, or photographs (paper copies of phots may be included). Any Any violation of a country's import laws or these instructions may result in serious consequrnces for the Church and the missionary involved.
International Reply Coupons can be sent, which the missionary may
exchange for stamps. These may be purchased at any US Post Office. To send any
other items that connot go by pouch, consider other options...."