One of my commercial customers brought me a fuel pump to replace on his scag. I asked him how much he paid for the fuel pump (from the dealer in town) he said it was over $400. He asked me how much I could get it for. Luckily, the part number was on the box it came in, so I looked it up that way.
But if I hadn't have had that box, I would probably not have been able to find it, because of not knowing the engine model number.
BTW, I found a genuine Kawasaki fuel pump, with matching part number for less than $200. I told the customer, I could get the part and install it for less than he paid for it at the dealership.