LinuxCNC 2.8 Buster on VM

Hi,
my machine is still using 2.8 with buster.

Now i wanted to setup a virtual machine to test some changes at home which i want to make. But if i run sudo apt update it shows me that linuxcnc.org/dists/stable/InRelease ist not available. In my sources list i use linuxcnc.org dist: buster 2.8-rtpreempt base 
i guess there is something like a archive adress but i don't find it in the documentation.. 

Also i would like to install the older probe basic version which i use on my machine. I dont want to change to 2.9 as there are too much changes and i don't even know if its running on my machine which uses quite old hardware.. But the documentation only shows the dist for the latest version with python3.11.. 

br