dnd 3.5e – Price for an item that lets you assume a single fixed disguise, as disguise self

The player of a kobold PC wants a magic item that lets them disguise as a gnome for convenience’s sake. I figure this should be a slotted magic item that works using disguise self. With no limitations, the guidelines would put that at 3,000 gp — but a single fixed form is obviously a huge limitation. I’m leaning toward a flat 1,000 gp. Is this reasonable?

N.B. I am banning/nerfing the Hat of Disguise for being disgustingly underpriced.