Rhythem Theme for Drupal Commerce
This is actually due to a change in Commerce 1.13 that we didn't have a great way to overcome initially. (More information at: https://www.drupal.org/node/2697017). The issue is with the settings for the product reference field on your node type. If you edit it, you'll find an options list limit setting that you can increase to see the more complete list of products again. Sorry for the regression. :-/