While there are APIs available to create services and subscriptions dynamically, the platform is not intended to create such objects at scale, due to several reasons, like the fact that once you add a service you should restart your Thing or Template, and in large Thing populations that takes time and it also has the side effect is that the Thing becomes disabled for that short period.
There are several posts touching this subject already - not sure if you searched the forum: https://community.ptc.com/t5/IoT-Tech-Tips/Create-a-service-dynamically/m-p/533118 and https://community.ptc.com/t5/ThingWorx-Developers/Modify-service-code-programmatically/m-p/515218
Also there's no duplicating API for Mashups at least, but you can do that very easy in a manual way if you get, change the name, then put back the entity as XML
