Boson Netsim 6 Userguide Boson Netsim 5.25 Simulator For CCNA ?

Boson Netsim 5.25 Simulator For CCNA ? - boson netsim 6 userguide

I would be glad if someone tells me where I Simulator Boson Netsim product, compiled 5.25 (version 5.25) in price / fair price.
I have the highest (v. 6) and lower versions, but not 5.25.
The reason for this particular version is that I am not satisfied with the other version.
Your help is greatly appreciated