Phil, you might have to do some searching on here for the answer and it would be a couple of years ago. What I did notice when mine were replaced is that the stern powr top cover had been held on with S/S bolts. These finished very close to the rams which had corrosion right next to the bolts. So now I don't bother with the top cover.
£600 from Lancing from memory, or the is a guy on US E Bay selling stuff, Ruddymart I think. Scary Des has used him before.
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