The colour match to Mercury Cloud white is an automotive colour called Ford - Wimbledon White.
For decals, go to www.nymarine.ca
As for painting tips of outboards there are many on the interweb. Here is one I found, following a quick search.
First rule of painting any surface of an Outboard motor that is going to be exposed to the elements especially salt water is preparation. You are going to need a few different grits of sandpaper starting from a course 120 grit to a 400 or even 800 grit wet/dry sandpaper. Start with a 120 grit to sand the entire Outboard motor starting just below the Cowling or top cover. Using a small orbital or finisher sander would work the best for removing the old warn out paint.
Take your time when doing the prep work and in about a day your outboard motor will look like it just came off the factory line. If you purchased pre-cut sheets of sandpaper you will save yourself a little bit of time but the cheapest would be buying full sheets of sandpaper and cutting it into quarter sheets. For the first step of sanding place your a quarter sheet on your sander and start sanding from the top and work your way down to the skeg on your outboard. Donít press to hard on your sander let it do most of the work as you donít want to etch any patterns into your outboard. When you have a majority of the motor sanded using the orbital set that aside and finish the rest up by hand. Note you donít have to get all the paint off just enough that all surfaces have been sanded throughly.
Repeat the same steps as above but now switch to a 200 grit on your orbital. If you have an air compressor keep the surface dust free as much as possible by blowing off the motor every few minutes. This helps keep the surface of your outboard clean and easier to sand and prolongs the sandpaper so it doesnít get all clogged up. When your done with the major sanding once again go over all the smaller areas by hand.
Finally get your wet/dry 400 grit sandpaper out and a bucket of water for your last step of sanding. Keep the surface of your outboard wet and go over everything by hand. This may be a step that you want to skip but this is what will give you that nice smooth mirror like finish on your paint job so take your time. You will notice as you sand the surface it will start to fell like glass which is what your going for. When everything has been sanded take your garden hose spray your outboard off and if you run your hand over the motor you shouldnít feel any rough spots. Now your ready for your primer paint.
Primer is very important to use as it helps to adhere your final spray paint to the motor. Hold your spray can of primer about eight inches away from the surface and remember to keep it moving when laying down your base coat. If you do have any runs or drips you can always wait till it dries and use your wet/dry sandpaper to smooth that down so donít worry if you mess up a bit it happens. When your outboard is completely covered in primer let it dry for about 3 hours in the direct sunlight. This will insure a permanent bond and help with final coat.
When the primer is completely dry your now ready to spray your outboard using your choice of spray paint. Donít rush this step as any drips and runs now will have to be sanded down so you get the professional look your going for. Your basically going to try and get 2 coats of paint down for your final spray, but unlike your primer you really only have to wait about 15 Ė 30 minutes between spraying. Make sure everything is covered take a really close look to make sure you have not missed any spots on your outboard while also make sure any holes that are on your case are not clogged with paint. If you do have any donít worry just take a paper clip bend that straight out and remove any paint. Now your ready to let it sit and cure. After a couple hours you can lay down your clear coat. This will really help protect your new paint job as well as your motor. If you have a white paint job it may be a bit difficult to see the clear going on but just like before keep your hand moving so avoid any drips or runs.