Just check coupons out (with price alert and history). Best price?
RGB light effect, can be connected, Each sword is powered by 3x AAA batteries (not included).
Aliexpress
I could not find it on Aliexpress. Click here to search by yourself.
Here are coupons that you can use.
Latest price update (UTC time):
Price history and price alert
Price history (for all/most countries) for YWXLight 2x Double Sided RGB LED Lightsaber is here.
Price records source(s): Gearbest
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).