This is a little different, but I think that you could do a great John Constantine from Hellblazer.
John Constantine - Wikipedia, the free encyclopedia
He's a occult detective and deals with a lot of weird stuff every day, and is a little messed up because of it. He's definitely a hero, but cynical and a bit of an ass. He's also rumored to possess some very powerful magic, but rarely seem to use it. Instead he tricks people and cons them into doing what he wants.
You are 6ft 4 and he's listed as 6 ft 0, which isn't that much of a difference really, especially considering that the comic is drawn in a way that makes it hard to really get a good grip of how tall the characters really are. Constantine has been interpreted in a lot of different ways, so being a perfect look alike would be difficult. In my opinion you have good facial features for making a version of him.
Some grease in your hair and some gunk on your face, and you'll have it down pat.
He wears "normal" clothing, so sewing would be limited to altering the garments to fit right. A trench coat, white dress shirt, a tie (red or black), a pair of dark pants and a pair of boots is pretty much his "costume". You'll need to distress and dirty these things up a lot. This is where the real work would be needed. He practically lives in that getup, to the point that loosing his trench coat is a major deal in one storyline. As such, having clean clothes is not that characteristic.
You should be able to find most if not all of the clothes in thrift stores, which would keep the budget down a lot. Research into what kind of trench he wears might be necessary if you want it just right.
He also smokes like a chimney. He's pretty much always drawn smoking, so it's a part of the character. If you don't smoke I'm not telling you to start, and if you do, I believe that DH has rules about smoking inside. Get some fake cigarettes.
Hope this helps!