No. You cannot just install signing tools. You have to install the Visual studio tools, VS 2013 update 3 which contains Windows Phone 8.1 SDK or install WP 8.0 SDK.
For Windows Phone company app distribution, you also have to precompile the managed assemblies before signing.
http://msdn.microsoft.com/en-us/library/windows/apps/dn168929(v=vs.105).aspx