I've got a superpro De dion bush in one of my alfettas, nothing bad to say about it - seems well made, stiffened the rear up a bit, and was cheap 
I remember trying to get those from them a few years ago with no luck, so am interested to hear how you go.The one bush Superpro don't list though is the 2 bushes on the rear sway bar. Not the ones that mount the sway bar to the chasis but the ones that connect the sway bar to the two links that are connected to the De Dion Suspension.
I don't remember exactly, I put mine in probaby 4 years ago.Fest the rear De Dion bush you had installed do you know which way it is suppose to go in as one side is different to the other or will it be obvious when I pulll my suspension out?