Power Supply adapter bracket

In round numbers what is the material cost of the goop or whatever you call it to make the connector?  Or is this the wrong question?

I ask because this is exactly where I see the hobby going.  For anyone following the Electrical Forum, there has been a recent (last year or two) flurry of activity in fabricating custom circuit boards.  It takes some skill and technical knowledge to design the PCB.  But once this is done, it then becomes a matter of fabrication which can be reduced to a fairly simple cost analysis of $ per square inch and how long you want to wait.

Likewise, I figure if the STL files are made available, how cool would it be that we get to the point where we can use OGR as the community portal.  Hence I'm curious if there's way to quantify cost.