Looking for replacement part for Ikea Hemnes shoe cabinet (white)

After our Hemnes shoe cabinet (white/two-door with drawer) suffered some damage during the move, I am now looking for the top shelf for this cabinet. Ikea told me that I cannot purchase this part there. Maybe someone has one "left over"? I would also appreciate tips on where I could get this spare part. Thanks!

How badly is it damaged? As far as I know, it is painted chipboard - so fill damaged spots, sand, and then paint [lacquer] white (or have it done).
Regards,
IKEA friend