From the little information I have with me, I show that the B-25 had 4 boost pumps, 2 fed the engines and 2 transfered fuel. If I'm not mistaken these pumps were made by Pesco, but I didn't find any part number.
Not all engines had fuel pumps attached to them. Somtimes either gravity or suction flow ensured fue flow to the engine. Manytimes you had a pump between the fuel tank and engine that ensured fuel flow during critical times if fuel wasn't free flowing to the engine, this is referred as a boost pump. At the same time there might be a neccessity to move fuel from one tank to another or to feed a left engine from the right tank. A series of valves and fuel boost pumps accomplished this.