[Simon J]

They won't be visible so you'll need to squeeze your hand in between the seat base and the seat back and feel if they are fitted. But if not, it's almost certainly a five minute job to fit them and your dealer should be able to find them in the parts list and quote you a price.

EDIT. A quick check of the Accessories catalogue for the 70 series shows that Volvo say that the ISOFIX cannot be fitted to the S/V/C 70 or 850. But as my 03 C70 has it as standard perhaps they enabled ISOFIX fittings at some point during production. The catalogue doesn't have a date on it. So best to check with your dealer.