Your T/C hawkens is not a traditional looking Hawkens so, why not use the receiver sight? Since it has the hole drilled and tapped in the tang I would put one on. That sight is a good one. I use one on both my T/C flinter and percussion rifles. And, yes, I do have a traditional Hawkens rifle and it doesn`t even come close to what T/C makes. I`m not knocking the T/C guns since I do have a couple of them and they are good shooters.
If, by some chance you would want a authentic looking Hawkens rifle you should be prepared to pay at least triple for a nice one compared to a T/C gun.