Vintage SBC 9-inch Diameter, 1.25-inch deep Pie Tin with Vent Holes, Aluminum

Vintage SBC 9" Diameter, 1 1/4" deep, Vented Pie Tin, Aluminum These pans (there are two available - price is for one single pan) belonged to my grandmother, who swore that the vented pans made a crispier pie crust. Makes sense, but my Pyrex pans are so much easier to clean! I have tried to find out what the SBC brand was, but have had no success. These pans date back to the 1930s or earlier, so whatever SBC was, that's apparently lost to history. My mom said her grandfather also used to swipe these pans to use for panning for gold! No success there either. Pans are identical, in vintage condition, with lots of patina. UPDATE: A fellow Posher believes that these pans were a premium given by the Sunshine Biscuit Company. I haven't been able to verify, but it's certainly possible!