I found hp's ftp site but not the actual location to the file. I would advise chatting with HP support and ask them the ftp link to the older software as they should be able to help. I have had them send me there for XP drivers that werent on the main .com website.
In case you want to poke around in their ftp site:
ftp://ftp.hp.com/pub/softlib/software10/COL18803/ja-51314-8/hpwja_setup-100-49299.exe
That is the link for 10.2, I tried backtracking but never found anything of value, I think they have the .exe files hidden.
"Silence is golden, duct tape is silver...