That's IoWSG Nightscape all right, Gareth. I suspect it's possibly a large and trial-ish type one.
Very likely, in my not so humble opinion, to be the work of Michael Harris, given the complexity of the swirls/ strapping laid into it.
A large slim oval shape, I don't think, was a normal production piece.
That would explain your extra feet. Because it's not from a normal production range, but because it's something a bit special.
(Waiting for John to shoot me down now. My book is not currently reachable to check.)