I have for sale the chess pieces and board mentioned above.
The pieces are dark brown and beige, and are made of plaster (I think). They are quite nicely detailed, and it looks like the original artist inscribed them "RJP 1997". Each player has:
8 x the Luggage
2 x Greebo (in different poses)
2 x Rincewind (in different poses)
1 x Nanny Ogg
1 x Magrat
1 x Granny Weatherwax
1 x Death.
The board itself weighs a ton (OK, 5kg) and is in an octogaon shape. The Black squares are denoted by an inscribed open book (presumably the Octavo?). The players' ends feature Great A'tuin, and the sides feature Death's face amongst a sea of hourglasses. The board bears (I presume) the designer's name R. Banks.
I will post some photos in a moment.
Andy