First, let me say that I don't have either of the X52 controllers, but I do have other Saitek devices, so that is why I have some Saitek drivers and SST files.

The big problem here is that it looks like the Saitek FTP site has fallen off the Internet within the last year. Perhaps someone can suggest an archive mirror of that FTP site.

I have a couple of SST packages that I downloaded in 2008 (no idea where I got them, but probably the Saitek FTP site). The filenames are sst_151205_32.exe and sst_171006_32.exe. For some reason Saitek was issuing some SST packages in this sst_ddmmyy_32.exe name format in addition to the other name formats they used. If you Google these filenames, you can see some discussion about the packages, and it looks like the sst_151205_32.exe package was the first to provide X52 support. I installed the sst_171006_32.exe on a 32-bit Windows 7 machine, and there are DLLs for the X52 and X52 Pro (all the files in the package have September 2006 dates), so this is likely an updated SST set for both joysticks and all the other Saitek controllers.

File sizes are around 17-20 MB. Here are the original FTP links if someone can point you to a mirror of the Saitek FTP site:
ftp://ftp.saitek.com/pub/software/sst_151205_32.exe
ftp://ftp.saitek.com/pub/software/sst_171006_32.exe