The answer is almost certainly yes. You could employ a userform to select the variations ane write them to various parts of the document, or as you have already gone to the trouble of creating the templates, you could add a ribbon tab to the ribbon with a menu system to call the required template.
Mail merge may create some issues in this context, but probably not insurmountable ones. We would need more information.
Start with
http://www.gmayor.com/Userform.htm and
http://www.gmayor.com/Userform_ComboBox.html