Here's what i'd reccomend for you:
1) Find the shallowest head that you feel comfortable using off the tee
2) Make sure the face is measured for loft and get 14-15* head
3) Make sure it is as square as possible to provide versatility in ball flight
4) Find a butt stiff, soft tipped shaft that won't balloon excessively on you when used off a tee.
The 4 above combined with the right head/shaft combo will be a great "double duty" club. Also, remember that even though it's a 3 wood you shouldn't be looking for the longest 3 wood you can find. you need one that you want to do 2 things:
1) Always find the fairway
2) Go a specific distance for par 5s i'm assuming
Hope that helps
PS A great head i have always heard good reviews about that you can pick up cheap now on ebay is the Nike T60 fairway woods. Despite the deeper faces on them, every review i have ever read said they are very easy to get up off the deck. Cheap experiment.