Yes, I do, but haven't found anyone else who does!
There was a milk version with plain chocolate in the middle and a plain version with milk chocolate in the middle. I even remember a mint version with plain chocolate top and bottom and a white mint filling in the sandwhich!
I wasn't being funny about Frys Five Centres Smurfy - and I agree with you that if manufactering became difficult, the popularity would have to be huge to keep them going - that's what I was trying to (badly) say- they were popular but modern day costs put the kybosh on them!