Chinook RV

I bought 2 lithium batteries for my 2004 Concourse. Can anyone tell me where I can locate the original charger. I want to replace it with a 12v to 12 v charger. Also hoping for a miracle that someone knows the make of the original.
I’m trying to help service center locate it.

The original charger was located in the "brown box" under the kitchen drawers. It was a Magnatek 7345, but many owners have upgraded the original with a new 3-stage charger, such as the Progressive Dynamics unit, which is available as a plug-in replacement.

Thank You. Parts ordered