I would simply use POST for this operation. Don't get overly pedantic thinking about which verbs correspond to which kinds of operations in a RESTful sense. Traditionally POSTs are to create an object - but in this situation, Occam's Razor applies - typically the simplest solution is the correct one.
If you want to use GET, refactor your request to put the parameters on the URI. A payload body in a GET request is not standard.
Additionally please see this SO:
How to design RESTful search/filtering?
This question is largely a religious/opinion-based discussion. The SO referenced above denotes the search itself as being a resource, and also correctly points out that mere use of a POST alone doesn't necessarily require that something be created in a database somewhere.