Hi there Dogbert. I'm having the same experience with my Galaxy Note 3 on Verizon. There's a good chance you've done everything correctly. I've downloaded the latest (correct) Google Play Services (-238), most recent Google Play Store apk, and Android Pay apk. I'm not rooted, and I've tried everything possible to get Android Pay to work (reboots, clearing data, clearing cache, specific activity launching, etc). When I open the Android Pay application, I'm greeted with the same pop-up that says "Android Pay is unavailable".