I had the best results in case I didn't only get mscordacwks.dll but also sos.dll from the client machine. I even had SxS issues with those files, so getting the files from the default .NET framework directory was not helpful either. Therefore I created the mscordacwks collector which gets all possible files for you.
However, you still need to find out which version to use. You can start by looking at the .NET framework version:
lm vm clr; *** .NET CLR 4
lm vm mscorwks; *** .NET CLR 2
lm vm coreclr; *** Silverlight
(In worst case, you have two different version of .NET loaded, in which case you are out of luck).
Once you know the exact version, you can load SOS of that version by full path
.load c:\mypath\SOS_AMD64_AMD64_4.0.30319.18444.dll
Note that the collected versions of SOS.dll will also be renamed to avoid file name conflicts. For more convenience, you can create a copy and just rename it to SOS.dll.
If there are still any mscordacwks.dll issues, you can proceed as proposed by @lowleveldesign. The tool should already have renamed data access files appropriately. If you find any bug, feedback is welcome.