What are the best products/tips for keeping my mouth wet while I run?

I stay FULLY hydrated (not a dehydration problem) and I run a mix of 800m/1600m/3200m for high school track. I want to improve my running times by keeping my mouth moist and not sticky from excess saliva while I run. (on both very hot and cold days) I don't need a stone/pebble in my mouth; gum either gets swallowed or makes the dry problem worse. What I am looking for is a $2 per race item or cheaper that will maintain wetness in my mouth. **Thank you very much for your time**