I would try going the used route... try looking at yard/garage sales or in the classified ads. If you have an industrial or government surplus sales outlet that's open to the public or a place that sells used office equipment, I would try hitting them up too. Thrift shops like Goodwill and Salvation Army may even have what you're looking for.
For instance, the desk I use is an older Steelcase similar to
this one (legs are different) that I bought from the surplus store of a local company. I'm pretty sure it sat on the shop floor, because it was covered in aluminum oxide dust (easily washed off), and was abused to the point that none of the drawers sat flush (most do now, but they don't slide as well as I'd like and still rub against each other)... on the other hand, it was only $5.