The Gallagio Raider’s Venture Co. Blasthammer should give the LFR appearance of the Capital Punisher, but it is instead giving the normal appearance (the Gallagio Raider’s Bilgewater Blasthammer also gives the normal appearance).
I bought and used both but only got the normal appearance. I tried buying it again on another character but it said already known even though I did not have the LFR appearance.
You can see this on the wowhead page for Capital Punisher as it shows both gives the same appearance.