http://www.ebay.co.uk/itm/4-GENUINE-NEW-SKODA-ALLOY-WHEELS-16-INCH-/200749853164?pt=UK_CarParts_Acc_Wheels_tyres_Trims_Car_Rims_ET&hash=item2ebd9fa9ec

I've seen these wheels pop up before and advertised as genuine octavia wheels. does anyone know if they are and what are the esential dimensions (offset, pcd, etc)?

many thanks

Yes, those are genuine octavia wheels. They were fitted to the Pre-facelift models (1998-2000/2001 in some cases). I believe they are 5x100, not sure about the offset but should be the same as the other mk1 octavia wheels

mu current wheels are 5x100, 43offset i believe but are 6.5inch wide. i need new bolts?

I dont believe you will need new bolts. At least down here (Barbados) the same bolts are used for steels or alloys.