If you come up with a style you like in Illustrator, you can save it as a Graphic Style to be applied later to whatever you like. In this case, you'd need a set of styles--one for each layer, but once it's done you don't have to mess with finding the colors or setting the exact stroke weights you wanted--Illustrator will take care of all of it. Also, you could reduce the complexity of this object by using only three layers: Background/sea with a solid fill, coastal glow with the centered stroke, and the landmass, with two strokes and a fill. The black outer stroke and the gold inner stroke can both go on the same object.

To add a second stroke to an object, open the Appearance window: Window>Appearance

In the Appearance Window, use the drop-down menu (to the right of the "tab". It looks like a down-arrow and three horizontal lines), and choose "Add new stroke." You will see a second stroke appear beneath the existing stroke in the Appearance window. Select that stroke and you can change it just like the original one.

To save your double-stroked and filled style, go to Window>Graphic Styles. Make sure the object with the style you want to save is selected, and click on the "New Graphic Style" button at the bottom of the window. Now you can select other objects and simply click on your new style--the objects will immediately gain the strokes and fill you specified.

When you've got all the styles you want, you need to save them so you can recall them in later documents: Use the drop-down menu again and choose "Save Graphic Style Library..." Give it a file name, and you'll be able to recall it again at any time using that drop-down and "Open Graphic Style Library>User Defined>(file name)"