Stateline Tack sells reflective gear for horses. I have a brow band (which
gets lost under the forelock of my Morgan!) and legs wraps. These are about
2-3" wide, are bright reflective yellow and wrap just above the pasterns (are
held on with Velcro). I bought two pairs so each leg is identified. I've also
seen reflective 'dangles' that you can hook onto your stirrups. I reflective
vest on the rider helps too!