Where can I find a 6 knuckle door hinge?

We need to find a 6 knuckle door hinge, to match-up to what was there before.

My mom has been getting her condo renovated, including getting new interior doors. It is a 30 year old condo building, the door frames are metal, and had a 6 knuckle door hinge. The hinge attached to the frame is soldered on, so rather than having to grind it out we are trying to find a 6 knuckle hinge so the half on the door can just fit into the existing hinge. (unfortunately the contractor did not keep the half attached to the doors before he disposed of them)

We can't find 6 knuckle hinges anywhere, seems the standard is 5, but that wont fit into the half that is still attached to the frame.