Chevin amp - op amp replacement

Hello,

I am in the process of revising my two a750s and two a2000s, since I have them I have had breakdowns with the bt139 triacs or small dead capacitors (on the 15v power supply).
But I have ignition "junction" noises on one of them, I want to change the op amp to see, but not easy to find..

Do you know what to replace ssm-2131 with? And also op42? (which can be found, but expensive..).

Besides, it's weird, I have an a2000 with op42 even on the front panel.
Do you have an idea of the original configuration? (if there is one).

Thanks!
Adrien
 
Hello,

I really can't find much.. I think I could replace with opa627 or opa828 but not easier to find (and not cheaper).

With a similar slew rate there is the tle2071 but the CMRR is not great..

Anyone have another idea?
Thanks