Hello, I’m looking for a QSI DC reverse unit. The picture is off of another site and I would like to find one for my Williams Daylight GS-4. MTH sold it as model 50-106. The reason why I am looking for this unit is so I can install the sound system by QSI for the Williams Daylight GS-4, which requires a QSI DCRU for it to work. If you have one, I would be greatly interested. Thank you.