I have a Primula cold brew bottle that I got from Amazon. Actually, I've gone through two myself (damn you girl who knocked my glass cold brew bottle off my desk at the start of my morning class, you made me suffer from lack of caffeine), plus have given two away as gifts because I love it that much. It's stupidly simple to use. I always use a dark roast bean when I do cold brew. Be warned, this caffeinates the shit out of your coffee.
Edit: here's the link for the bottle I use for $18 on Amazon
In case it's helpful, it was cheaper in the long run to just make my own with this small, easy-to-use travel bottle, a cheap grinder, and beans*. It was especially handy when the lines were long or when I was a little late to class. No worries if you're trying to spend DineX, just figured I'd suggest an ultimately faster and cheaper alternative!
*First from Giant Eagle before I discovered Prestogeorge in the Strip and went full coffee-snob for a bit. Since cold brew beans don't have to be the freshest, I only went around once a month in undergrad.