Oak Leaf via Amazon offers its Oak Leaf 9.8-Foot 30-LED String Lights 2-Pack in several colors (Warm White pictured) from $6.89. Coupon code "USECODE9" cuts that to $4.99. Plus, Prime members bag free shipping. Outside of the price below, that's the lowest total price we could find for this quantity from a U.S.-based seller by $4, although we saw these light strings shipped out of China for $2 each last July. Each string requires a CR2032 battery (included).
Don't need them soon? Allstar-Seller via eBay offers a 1-Pack for $1.89 with free shipping. It ships from mainland China and may take up to eight weeks to arrive.