Hi Dipesh,
1.Any IOS which has K9 (3DES) in feature set will support SSH.
e.g c3750-ipbasek9-mz.122-25.SEE4.bin
c3750-ipservicesk9-mz.122-25.SEE4.bin
c2950-i6k2l2q4-mz.121-22.EA12.bin
c2960-lanbasek9-mz.122-25.SEE4.bin
2.I think Cat2924 & Cat2912 does not support SSH.
3.These switches may have existing IOS as complete differernt. If to configure SSH you need to change the feature set , you can charge the client for feature upgrade, if client does not have license for that feature set.
4.Speak to your Pre-sales & Sales representative before putting this across the client.
HTH...rate if helpful..