Customer has an existing Cisco 2925 Router and he wants to make it SRST Router. I tried to find something on 2925 but I am not able to find anything so I am assuming it is end of life. So, question is if I send him the SRST licensing, would he be able to make it work?
It's a typo in the doc, there are no 2925, only 3925s.
Cisco never made a router model 2925.
Take "show version" to know what model is that, or read the label below or on the back of the unit.