Reflex-
I bought an Eveready headlight from Wal-Mart last year for $12. It's lightweight and does a fine job.
I've never thought that a light does much to spook deer. Ever seen a "deer in the headlights"??? When you're coming into the woods in the dark, deer can hear you, smell you, and see you even if you don't have a light. Using a light allows you to get into the woods as quietly as possible. A light isn't a disadvantage at all if you ask me.