Cheap flash that works remotely using ETTL with the ST-E2? (eg Yongnuo)

[dubcat]

Hi, I have a STe2 wireless transmitter which I use with my 580 ex II flash. I also have a sigma dg500 which works as a second flash with the same setup. The sigma is old and a little unreliable. I need a cheap replacement. Do Yongnuo make anything that fits the bill?