Here I found two still working links:
wintox_win32.zip and wintox_win64.zip.
No any source code, only compiled binaries, and this is standalone and portable exe-cutables.
You can find this in this zip-archive in ./wintox/wintox_original/-folder.
wintox.exe (x86, win32), this is oldest known version of uTox, which can working on Windows XP.
This was been released in 2014 year, and not supporting calls, and video calls,
but this program have a small size, supporting assymetric NaCl encryption-decryption,
and this is a p2p program, it can find a peers and connect them,
even in LAN, without connect to Internet!
Now, with my additional scripts, anyone can generate his modified wintox.exe
with custom nodes and ports.
Only two nodes available there, because too small size to rewrite in exe-hexdump.
In future releases, I'll try to rewrite this scripts for uTox v0.7.0, which is too working on Windows XP.
Best regards, and enjoy.