This is the Troy Alpha rail with built in sight, I have the VTAC mounted light on top and a VTAC sling mount next to the receiver.
Depending on the optic and laser, I think you could mount one there too. LaRue makes their LT135 scope mount that sits a little higher so a PEQ laser will ride up top too.
http://www.laruetactical.com/larue-tactical-sprm4-193-mount-qd-lt-135