A Super Blackhawk is NOT a flattop. Although the top of the strap is flat rather than rounded like a Vaquero, the Super (as are all non flattops) is distinguished by the raised rear sight protection. A flattop is flat all the way to the rear with no change in thickness.
A 10 inch Ruger 44 OM is more likely a flattop than a Super, 10 inch barrel lengths were not a catalog item for 3-screw Super Blackhawks, but was for the flattop. I see that Ruger shipped at least 2 10 inch Supers, but not more than ten, as there were only ten 10", Brass framed 6-1/2 and 12 inch altogether, where 92,450 of the S47's were made.
Values are not far off current model prices in many cases, usually less. The value of a 10 inch SBH might be more than we have in our pocket, however.