I'm pretty new to this forum myself so maybe not best placed to advise but if it were me then I would be looking to build from scratch rather than buy an off the shelf machine & then start hacking it about trying to make it suit your requirements.
If you start from scratch you can built the machine to the exact specification you require for your project. Don't know what your aim is but you may find that most parts from the off the shelf machine are not suitable for your need which is then just a waste of money.
It all depends on what you want the machine to do, pick & place could mean almost anything lol.

Even with a limited supply of tools it is possible to construct a machine with a bit of help, even if you bought an off the shelf machine you would have the same problem trying to modify it.

There are plenty of people about who would be able to machine parts for you from what I have seen so far, when you say Gerber files are you using something like Omega? If so as long as you can export as a DXF, EPS or ai vector file which you should be able to do then someone will be able to help.