The shell construction and the way the reinforcement hoops are glued up seem like early Ludwig & Ludwig, pre-Conn era, to me. The drum looks like its had another badge on it before as there appears to be two vent holes? And that is definitely not the original throw-off and butt. The butt looks like 50's Slingerland as well as the throw-off. There are extra holes that have been filled that look similar to one of Ludwig's early throw-offs from the 1920's. You might actually have a 1920's Ludwig & Ludwig snare there, not a Slingerland, and it definitely is NOT a WFL.
L-D you may be right, the screws don't look slingerland and the professional didn't come in a 15" at least not a stock size, and the re-rings don't look slingerland either,
