Sure, you can embed a resource in your DLL. Then at runtime you just do:
Stream stream = Assembly.GetExecutingAssembly().GetManifestResourceStream("com.stackoverflow.plugin.example.Foo.pdf");
This would give you a stream to the Foo.pdf
file embedded in your DLL. Pay attention to the fact that the resource name has to be scoped by the namespace of the type from which you're invoking the method.
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