No. Factory fresh-air A/C (integrated with heat and defog, with the slim underdash A/C outlet duct) was introduced in the middle of the 1965 model year. The bigger/boxier unit you're describing is Mopar "Cool-Aire" add-on air conditioning, which was not an integrated fresh-air system and was available as an accessory on A-bodies starting in '61. It remained available as an add-on accessory even after the integrated system went on offer in '65.