Just spent half-day trying to figure out it.
Once again sucked without any success. Concrete5 lacks of good documentation, and code structure are horrible. Page list view gets pagination from it's controller, controller get from core search src, src calls Pagerfanta\View\Template\TwitterBootstrap3Template. And this is the part there I get lost. Even if you find it out, probably you won't be able to extend it without modifying core. It looks like simple task, but unfortunately new C5 can make it in most complicated way:(

Hi Zavoodi,
The $pl variable in the block view is just a straight pagelist, so you can add a template or override the block view and just run:

to change the pagelist to show 100 entries.

Best wishes,
Korvin