I think probably you can use properties placeholder and ConfigAdmin OSGi service to replace source and destination url during runtime.
You may need take a look at camel-osgi example shipped with kit to get more details how to use properties placeholder in OSGi container.
Yeah using the model API (xxxDefinition) you can create a template for a route. And use that to create new runtime routes.
Then you can just change the endpoint URIs of the model before you create a route.
CamelContext has API.
And you can use a RouteBuilder to create the template route, or do it manually using the xxxDefinition API.