Amazon offers the Lukati MFi certified 4-foot Lightning cable for $7.95 Prime shipped (free trial) with promo code SUKDYEXC. All other buyers will need to spend at least $35 to bypass shipping costs. That’s $12 off the list price and is $10 under the going rate for a (shorter) Apple Lightning cable. Amazon customers have rated this cable 5/5 stars.
This product includes a one-year warranty.