Be carefull: actually by putting "10" here, when the application will grow, you'll have to track down where you've put "10", "20", "35" (because the client changed his mind 5 times, but nut for the same pages averytime).

Make your repository as a service, then put that "10" in configuration of your bundle.
Validate your configuration.

Begin by reading that: http://symfony.com/doc/current/cookbook/bundles/extension.html
Then, you can see how it's done here : 
1. put your configuration: https://github.com/saro0h/playground/blob/kata-event-listener-config-test/app/config/config.yml#L77-79
2. Validate it: https://github.com/saro0h/playground/blob/kata-event-listener-config-test/src/Playground/DemoBundle/DependencyInjection/Configuration.php
2. Add it to your service: https://github.com/saro0h/playground/blob/kata-event-listener-config-test/src/Playground/DemoBundle/DependencyInjection/PlaygroundDemoExtension.php#L23-24