Something like this should work: http://www.amazon.co.uk/port-HDMI-DV.../dp/B000NHBLK8
Run HDMI from the PS3 and the V+ to the box, then DVI + discrete audio cables to the TV. Ã‚Â£30. Cheaper than a new TV.
The spec isn't entirely clear in this description, so it's worth confirming with the supplier that it can be used in this fashion first.