G.L.
Throw the party, and then consider this - instead of giving her a gift now, collect money/items from the team so you can send this mom a care package from the team every two months during the deployment. Gather information about what sorts of things you are allowed to send, and what would be most appreciated where she is going. We had one friend who was over in Saudi Arabia for a year - we sent him small toiletry items, baby wipes (very useful if you're out in the field), his favorite candy, and his favorite hot sauce. Things like the Starbucks VIA packets or packets of good tea are often appreciated. If she won't have access to skype where she is, prepaid phone cards are good (find out which ones actually work where she's going first). Also, find out what you can do to help the daughter while mom is away. One of the best gifts you can give to this mom is the assurance that someone will be watching out for and helping her child while she's gone.