I would advise you to take the advice of the previous posters.
While the condition of the Python is not stated, your Python could be worth $800 to $1000, while the 1903 (I am assuming a Pocket Model Hammerless and not a hammered Pocket Model, which is worth a lot more than a Hammerless) is a $300-$350 gun and the Cobra perhaps $350-$400, although a lot go unsold at those prices. (An early Cobra would be worth a lot more. What is its vintage? "First Generation" is an abused term that is often applied to any Cobra without a shrouded ejector rod, whether a 1950 gun, or a 1971 gun.)
The leather is worth practically nothing, just like used scopes.