Hi Brad.....welcome to TFF.
Your Colt Huntsman was made in 1964. The value, according to the Blue Book is:
90% - $250
80% - $200
70% - $180
BTW....whether this gun is registered or not has no effect on it's value.....and since I believe AZ has pretty liberal gun laws, it has no effect on your ownership of it either.
Take it out and shoot it & enjoy it!