DM74LS125AN from Onsemi is a discontinued buffer IC with no official replacement listed. However, there are a couple of alternates from Texas Instruments that could work in its place:
The TechForum Cross Reference category is for parts that Digi-Key does not sell or parts that have gone obsolete. Our Engineers and Techs have reviewed the specifications for these parts and made a recommendation for a replacement. Please review the suggested part to ensure it will work for your application.