Have you thought about an AMD Ryzen processor? Unless the end user is mostly gaming or using some other predominantly single threaded workload (even games are going multicore though) and needs every frame, they are much better value and much more future proof, since they run around Intel in multitasking capabilities. A Ryzen 1700 is CAD $373.99. It also comes with a good cooler so you don't need a separate one. Double the cores and threads and it can be easily overclocked to somewhat lessen the single core performance difference.
Another thing to think about is the CPU socket. AMD's AM4 will be around till 2020 so you can upgrade CPU. Intel's 7700k is on the LGA 1151 socket that will probably be phased out soon (Intel likes to switch sockets all the time). So an upgrade would require a new mobo as well.
Another thing to think about is the CPU socket. AMD's AM4 will be around till 2020 so you can upgrade CPU. Intel's 7700k is on the LGA 1151 socket that will probably be phased out soon (Intel likes to switch sockets all the time). So an upgrade would require a new mobo as well.