Asmodeous,
Old Model Single Six Convertible [three screw]...? ?
Old Model Super Single Six Convertible [three screw][Adj. Sight]...? ?
New Model Single Six Convertible [two pins]...? ?
New Model Super Single Six Convertible [two pins][Adj. Sight]...? ?
Actual markings on frame...? ?
"*" or "R" or "S" stamped ahead of trigger guard on bottom of clyinder frame...? ?
Last three digits of SN on both cylinders...? ?
Barrel length...? ?
Then, maybe we can give you a value....! !