Have you tried contacting Andy at The Bosun's Mate? This page from his website suggests he can supply most outboard paint colours: http://www.bosunsmate.co.uk/bargains2.htm
There's a guy on ebay that can get you a can in any colour you want. I bought a can of Mariner grey not so long ago from him. I think it was about £10 with postage.
Try a local Automotive Paint supplier,If you take the engine cover or some other part they will mix the paint in aerosol for you to the exact colour,try a Partco branch or someone simular.
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Never be scared of the sea but always respect it. www.aquasnaps.co.uk
Or a good car body repair/paint shop one of the bigger ones, those guys have a good eye for things like that a lot of them mix the own paint these days, so would flog you some
And in the east, Fourth Yacht Marina, (FYM) Grangemouth. 01324 665 071.They're open Sundays too. I've bought it from them in the past.
There is a standard car colour which is so close you'd be pushed to tell the difference. I've also used that. When I'm in the workshop I look it out and report back.
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OK, the grey were're talking about is Mariner Light Grey, it says on the tin and the very similar colour is Rover Gunmetal Metallic bought in the local garage for a couple of quid.
I used ford pearl grey metallic on a yanmar diesel in a sailing boat and it was near as damit,in fact the dealer told me to use it rather then pay yanmar prices.
I however bought some yamaha touch up paint for my f100,and it was nowhere near???
