I just purchased two
Alexa Voice Remotes for Amazon Echo and Echo Dot at $9.82 each, sold by Amazon Warehouse Deals. They are listed as "Used - Very Good: Very minor cosmetic imperfection on the item." This is an excellent price, as they cost $29.99 new.
I use my remote all the time with Echo. It's much easier/more pleasant to speak commands via remote than yell at Echo (especially when music's already playing). It has volume/skip/play/pause controls as well.
Right now, there are still some at that price. Here's the link:
https://www.amazon.com/gp/offer-listing/B01E9AHU8Q