Yes you can although Provape recommends AW, great
batteries and it's not worth saving a buck or two for something else imo.
As far as the battery size, the first 2 digits 18xxx designate the diameter of the battery. The second 2 digits designate the length in mm, so 18500 is just 1mm longer than 18490.
Edit, make sure it's a button top. I've seen post where people have tried flat top and the positive didn't make contact.