samuelspark :
I thought the fans had to be similar?
There is nothing exotic going on. If it is a 120mm fan, it will fit physically.
One issue will be how to power it.
You might buy a splitter if you intend to vary the fan speed via motherboard control.
The simplest would be to plug it in to the psu and run it at a constant speed.
If you have not yet built the rig, I suggest you just try the supplied fan first.
If you think you need more, it is not hard to do so later.