How to integrate Lockr encryption key with Ubercart credit card payments
A kindly developer wrote a patch for Ubercart that integrates Lockr key. It's working great for me. 

You can find the patch here: https://www.drupal.org/node/2842813

Note: it's written for version 7.x-3.9 which isn't the latest, so it may have to be modified and rerolled for the current version.