Based on everything I see on this machine…
It’s a Kirby 513.
Nozzle and Headlight trim appear to be original. The grip is correct as the early 513s had those older grips. But the grip sleeve is an aftermarket. The belt lifter is an aftermarket. Cord is original for the 516 - 561. The emtor tray could be original, but it seems like the shade of grey is too light, unless it just faded a lot. The bag is a Classic 1CR/Omega replacement that had the top portion cut down a bit, and a metal slider from an open top bag fitted onto it. One front wheel is for a Heritage or Heritage II, and the other is for a Classic III. The rear wheels are red replacements for D80 and older. This is quite the frankenkirby.
This is a personal opinion, but I have a feeling whoever bought it may have only gotten it for the cord, as that is a desirable original cord for models 516 - 561 as I mentioned above. But hey, maybe the buyer actually wanted it for their collection, and or to restore. Who knows.