It is a sport, we bought ours in september 2000, an end of line cheapie!.
We are still on our original seat but think a spare would be prudent. We tried a seat out of a peter lynn comp which was a good fit, being adjustable for height & just fitted in with our backrest.
The foam roll supplied on the backbar is painful, we bought an abroller from Argos & used the headrest as a backrest in the buggy. It was a couple of years ago but you never know, the abroller is made of black steel tubing, covered with some black foam & some green foam, probably the bit near the headrest which is grey. Cost £17. Get the right one & the bracket screwed onto the back of the headrest will fit straight onto your backbar as the tubing is the same size, it pivots which is nice, is unobtrusive for going backwards & I held it in place with a couple of jubilee clips either side of the headrest bracket. The plastic will come off at the corners but duct tape has held it for two years!.
Richard.