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Yes, you can install a threadless fork, but you'll also have to replace the headset with a threadless headset and use some kind of compression. Depending on what compression you go with will determine what kind of clamp and bars you can use. So, yes, you can do it, but it's a lot more involved than just replacing the fork.
The Fasen Raven uses an IHC fork and IHC compression with a standard diameter clamp and standard diameter bars. You wouldn't be able to use any oversized bars without changing out your fork, clamp, and compression system.
If you have an external clamping mechanism (ICS, IHC, HIC), then you need a slit in your bars. Without the slit, the bars will resist compression and the clamp will do nothing to squeeze the bars against the fork or shim. The slit allows for compression of the bars. This is not true with SCS as you want the bars to be solid and resist compression since there is nothing inside the bars.