Several companies sell rails that attach to the carry handle. As well, several optics manufacturers like Aimpoint and Trijicon sell carry handle mounts for their optics. I would encourage you to save your money for a rifle with a flattop upper receiver/removable carry handle. The problem with carry handles is that they are very high, and mounting optics on top of them drastically increases the height of the line of sight of the optic. This is not ideal for reasons of accuracy, no/poor cheek weld, and the ever common craning of the neck which leads to neck pain during extended use.
If you don't mind me asking, what is your budget? Which rifles have you looked at/are you considering?