You can store the Smart Signature (Stateless ASC1) address as global variable in the Smart Contract. Take a look at this article to read more about the topic.
Remember that with the AVM 1.0 linking Stateless and Stateful components is no more needed! In fact, with the AVM 1.0, Applications have both an Application ID and an Application Address, so that you can issue transactions directly from the Smart Contract. So, for example, you can execute an Asset Transfer directly as Inner Transaction, without pairing the App with a Stateless ASC1.