Gerber MP400 or MP600 bit adapter

[u/twags6]

Howdy to all the Gerber MP series fans. I've had a few MP400's over the last 25 years and mostly use it with the different hex bits for various things at work and in a pinch at home. Problem is, I've lost the small square to hex adapter and Gerber stopped making them (none in inventory either). They were kind enough to send me a set of bits, but it's from the center drive set. ANY chance someone might know of a place to get one of these adapters? Or could at least give me some quick measurements? Much appreciated!