If you have friends in corporate, they can get in touch with their IT department, who would have the contractors and vendors details for this.
Also, some companies give old systems to employees itself; without the hard disk / SSD for less price. Most don't though.
You would find a lot in Chennai and Bangalore, there are reseller mafia gangs for these in hoards in IT hubs. Selling kind of obsolete stuff for a premium.
I had my friend get one from a vendor in Kamanahalli, Bangalore for a thinkpad and just popped in a SSD to get it to work as a browsing and word / excel system. Still running fine.
However, I would recommend to assemble one for cheap and enjoy the long warranties from a cheap build.
Is there a budget that you have in mind? Also the usage? Based on that we can look for the required options.