I picked up an engine for free yesterday and it has a carb that I have never seen before on it.
It's a solex centre mount but it is dual throat. The base of it is rectangle where it connects to the manifold but there isn't any stamping on it to identify the model (I have to clean it up to be sure). I'll click a pic of it tonight as I want to identify it.
The engine also had an 009 and a spin on oil filter attachment as well - not bad for free!
The crank pulley keyway is munched though - hope it's just a stock crank!