You'll have more in the next Stable ROM for your device. Your device is a Global-exclusive, so it doesn't have a Weekly ROM that gets updated regularly.
You can't add more Super wallpapers the usual way, they are hard-coded in the Super wallpaper picker.
You can install them manually (APKs are available on APKMirror), then launching "Live Wallpaper Picker" using Activity Launcher and setting them from there.
It's a bit of a hack, but that's the best you can do for now.