Is there anything to be gained in there? Yes, you need to see if there is a dead air space above the top lip of the vent. If there is, you need to add a baffle at a 45 angle to increase the air flow out the vent, even with fans.
The Whirlpool units I listed above are exactly 65" tall when you take the wheels off. You gain 3/4" when you cut out the board across the top that holds your unit in. If you have 1" space above your current unit in the slide, you will have the 65" needed for one of these units by removing the 1 & 3/4" of wood above your unit without lowering the floor. It is not counter depth so it's not going to come in the door.
Granted they do not have ice on the door and they are not three door... two door with the freezer on the top. I looked for years before I found one this short over 16 cuft.
Unlike the Samsung's that have DC compressors and run fine on MSW power, I would add a 500W PSW inverter to run any refer with a AC compressor.