A lot of guys have gone out an purchased their own stock(VLTOR, LMT, etc) for their C7/C8 rifles aswell as pistol grips, vert grips, RAS handguards and lights. And a lot of guys have gotten their own sights such as EoTech, Aimpoint, ACOG, schimdt & bender, etc. Aswell as iron sights like the carrying handle/iron sight aswell as fixed an folding BUIS.
The C8 is now issued with an EoTech sight; some places will issue the C8 with the C79 Elcan aswell as the EoTech.
And for the IR laser stuff; the CF uses the PEQ2 and PAQ4. Also we get the M3X Tactical Illuminator flashlight to mount on our rifles.
Here's an example of a standard C8A1 and a C8SFW with personal add ons.
http://www.gun-world.net/USA/M16/diemaco/c8_sfw.jpg
The new C8A3 rifles come standard with
regular/standard plastic handguards, pistol grip an stock in a OD colour
OD Cadex folding vertical grip
EoTech 552
Diemaco/Colt Canada BUIS
And depending on the unit you would also be issued the M3X light and a C79 sight.