Modules that will allow search for external data using either Apache Solr or Elastic Search I have data within a Teamsite application which we will be indexing within either Apache Solr or Elastic Search (have not decided yet).  I plan on creating search pages within Drupal 7 that will allow the user to search against the external indexed data mentioned above and list the search within a Drupal results page.  

Are there any Drupal 7 module that will allow this to done for external data using either Apache Solr or Elastic Search similar to what can be done with Drupal 7 modules that connect to Solr or Elastic Search for Drupal indexed data?
You need Search API with either of the plugin modules. Search API is a fantastic way to abstract out the engine from the logic. Although I've only use the Solr implementation I've spoken with several developers who have switched to Elastic.


https://www.drupal.org/project/search_api
https://www.drupal.org/project/search_api_solr
https://www.drupal.org/project/search_api_elasticsearch


Search API also works with Facet API (which supports the ApacheSolr module too -- the 'competitor' to Search API).
https://www.drupal.org/project/facetapi

In Drupal 8 those two modules (Search API and ApacheSolr) have become one.