My wheel arches are in a bad way does anyone know of a repair panel? :-/

You need to look at the inner wing where it meets the outer section too cos that rots like hell and makes it a very expensive repair if they are rotten too. It does sound to me like they will be gone too by your use of the 'rotten' word.
To be honest m8 I bought a set fro Germany because they were described as being top quality and available precoloured or primed or Chromed. I paid 80 notes for them but they turned out to be absolute sh*te.
My advice would be to go to any decent bodyshop or bodywork repair supplier and ask them for advice. There are some very good ones made in this country but I have lost contact with the ones I used to buy from. Retiremernt has its problems :( I am sure that they will be available somewhere...Just do not use the ones from Germany I got of Ebay. They were like tin Plate anyway and would not have lasted long.
:y