What is the "ember way" to make straight rest calls

I [mostly] understand the ember-data paradigm of defining models and then manipulating them. However, I’m not sure how to go about performing a lookup for validation purposes. Do I define routes and models for all the participants just so I can do the lookups?

For example, say I have an Event, which requires a Person, a Place, and a date. I want to create a screen that allows the user to enter an Event, but I want to validate that both Person and Place exist before accepting the input. Naturally, I’d like a real-time validation, but there are too many options to offer a drop-down or even an autocomplete. So I wire up an action to check after the user enters an id. Would I check for something like this.store.find('person', this.my-form-bound-id)? Or, would I need to get the model for the route and somehow pass the id to check? Essentially, I just want to check that /person/n returns a record.

That is a specific app problem. That solution is as good as any.