If you dont need to have topo maps loaded on it, I would recommend any of the Garmin eTrex series GPS's. As long as you have a GPS with 12 parallel channels, you should be able to receive satellites even through tree cover once aquired. IMO, Garmin is the best in the business. I've been using GPS's for over 10 yrs. The one below is the same one my wife uses and she always finds her way home.
Cabela's -- Garmin® etrex H GPS Unit