I think your item is either a teapot or (in my opinion) a creamer for a childs tea set !! Many were not marked and they came in all sizes depending on who made it !! I have seen the teapots as small as yours and I have seen them larger at 5 to 6 inches tall !! Since not all were marked ,,usually just the box it came in had the makers name,,you might keep a watch on ebay for a similar set !! Yours is likely mid century !!