Hi Spyros-

I actually built mine using new Molex parts. They were bought from DigiKey, Digi-Key Corporation - USA Home Page on line, using the exact part numbers spelled out in the pdf document that Ron so conveniently provided above. Note: be sure to buy the gold plated pins to avoid corrosion issues. All that said, recycling the connectors from a spent battery pack will work every bit as well and save you a bit of time & $$$. I just wanted to build up some spare packs & test items and did not have enough spent packs to recycle.

As far as the 9v battery clip goes, you can get them from DigiKey as well, but they’re common as dirt just about everywhere- I bought mine locally.

Ken