It appears as if most, if not all, of the archive.org material was uploaded on June 2, 2014:
https://ia902503.us....ainPenCatalogs/
https://ia902508.us....ensCatalog1923/
https://ia802506.us....ServiceManuals/
EDIT on 8/6/2014: It looks like additional material is being uploaded. The latest being on August 3, 2014: