You can not really limit the selections if it is an enumeration. You may be able to do this with a widget from the appstore or with some custom built widget, but there is no out of the box solution.
On a reference selector, you can constraint the selectable objects in the properties. You can use xpath or microflow. Please not, that xpath will only work, if your stuff is stored to the database. Otherwise, you need to use microflow to create the list of selectables.
Depending on the solution you chose, you need to refresh the page when you make a selection (onchange event) so that the list of selectable objects gets refreshed as well.