I've had this game for many years but not played it for a long time. The box is fairly bashed, but the pieces inside are in very good condition. There are only 5 cars (I think there should be six) - but these 'cars' can be bought from the following:

https://www.ebay.co.uk/itm/255848711591

This is quite a heavy item to post so it will be packed well for the journey, if you win the bid.

See https://www.ferti-games.com/pitchcar for more information. Or check out ebay for other 'PitchCar' expansions or parts.