Repo for updateso to an old SL

[Elio Fabri]

Hi all,
I'm stil using SL 6.2 (waiting for the fog about future SL, CentOS ... 
to dissolve).
I'm in need to update firefox. A version for RHEL6 systems exists 
(firefox-91.4.1esr) but yum finds no repo for that package.
Some help? Thx
--
Elio Fabri