LightInTheBox offers this 44-in-1 GoPro Camera Accessories Kit for $28.70. Coupon code "SO4808729" drops it to $16.70. With free shipping, that's the lowest total price we could find by $8. The kit includes a chest harness, head strap, monopod, wrenches, and carry case. Deal ends October 20.
Note: Uncheck "Add Shipping Insurance to your order" during checkout to remove the 49-cent fee.