Digi-Key carries a vast number of fans. Many, like AHB1548GHG have gone obsolete, but have no fear, we have a replacement.
AHB1548GHG is a brushless DC fan made by Delta Electronics which went obsolete in 2014. This can be replaced by either EFB1548XHG20D or OD172SAP-48HBXC
If there are any questions on this, please reply to this post and we will be happy to address them.