I recently received my first few fountain pens (early inheritance from my father in law, along with a whole mess of vintage SRs). I have one that I'm trying to rehab, and I need a new sac for it. It's a lever-fill Sheaffer. I can't find any serial numbers, model name, or anything else. The imprint says "W.A. SHEAFFER PEN CO/ PAT AUG 25-08-FORT MADISON, IA. USA/ DEC 10-12-JAN.27-OCT.20-NOV.24-14" Pic attached. In the pic, the pen looks brown, but to the naked eye, it looks black. Thanks in advance.