Apple Watch Nike Series 5 (GPS + Cellular) 44mm Space Gray Aluminum Case with Anthracite/Black Nike Sport Band Space Gray Aluminum MX3A2LL/A - Best Buy
Apple (Canada) - Take Nike + iPod on your run.
Nike/Apple Fitness Sensor (iPod or iPhone) | eBay
Amazon.com : Nike+ Stand Alone Sensor Kit : Nike Plus : Sports & Outdoors