Thanks a lot guys!
Here is what I found as far as support for radiators for HAF is concerned:
"Top: 360 / 240mm x1 Rear: 140 / 120mm x1"
So, I guess I have 2 options: either go for H115i and do some case modding, or I go for one of the following 240mm models of the same item:
either Corsair Hydro Series H100i v2, or Corsair Hydro Series H105.
These are obviously smaller, but should fit without any modding needed.
The last one is thicker, which is supposed to give better cooling performance.
So, what would you do?