You could always talk to your LGS owner and place a request into him. Tell him what you want, age, condition, finish, barrel length, your wallet depth, etc., maybe spot him some money and/or tell him if one comes in that meets your criteria, 1st dibs, etc... If it doesn't float your boat, he can put it in the display case and it'll probably be gone within the week.
Most any Python is better than no Python and they're all gonna cost a small fortune. Gotta plan on spending around $1.5K minimum, maybe more, maybe less.
A free people ought not only to be armed and disciplined, but they should have sufficient arms and ammunition to maintain a status of independence from any who might attempt to abuse them, which would include their own government." - George Washington, January 8, 1790, First State of the Union Address