If you click the right links at GPS City you'll get a list of handheld GPS, pages of handhelds. There are quite a few eTrex units listed, I like the Vista HCx, but on your budget, the Garmin eTrex Venture HC would work, I just don't like the bright color of the case. It would be hard to lose it though.

Take spare batteries and don't forget to take a map and compass too.
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Better is the Enemy of Good Enough.
Okay, what’s your point??