Don't you mean a Hummel? If I recall, the Wespe was a tank destroyer with an 88mm gun, along with the Nashorn, mounted on a Panzer Mk.4 chassis. The Sd.Kfz.165 Hummel was a self propelled 105mm howitzer.
If so, Model Card made one (NR 43). I've only seen a pirated scan, but the overal quality...