The first version of the SM A5 used one SM tantalums and two thru-hole electrolytics.
This version of the A5 does not have the leakage problem.
This was used for a few hundred scopes starting at s/n B050000.
You can look at the d/c on the devices of your 2465 to date it.
But on a 2465 there is no need to ascertain a mfg date, unless your just curious.