The winged disk in Ancient Egypt usually represents the god Horus-Behdety, and yes it is known from the Old Kingdom.
I couldn't find any references online (other than the Wikipedia article) to monuments created by Sneferu which include representations of Horus-Behdety. However, the earliest representation is supposed to be in a carving in the Step Pyramid of Djoser at Saqqara.
Alan Gardiner's paper Horus the Behdedtite, published in the Journal of Egyptian Archaeology in 1944 discusses the development of the winged sun-disk in Egypt from the Old Kingdom to the Ptolemaic period, with a number of examples that pre-date its use by Shaustatar, King of Mittani, in the 15th century BC.
EDIT
I found a 2014 PhD dissertation on Horus the Behdetite, by Randy L. Shonkwiler, which identifies the earliest confirmed use of the winged sun-disk in Egypt as being on the 4th dynasty coffin of Queen Hetepheres (~2500BC), who was the wife of Sneferu and mother of Khufu.
In addition to the image of the coffin included in the dissertation, a quick Google search found this image which clearly shows the winged sun disk inlayed on the end of the coffin.