Some additional details to help the group buy:
Today's exchange rate the price is $3736.50 retail. So assuming the price would be less than that.
And bullet points from their website:
https://www.classicretrofit.com/collections/electric-air-conditioning/products/air-conditioning-kit-for-classic-911-full-kit
All Electric. All modern components
Weighs around 30 lbs (14 kg)
Fits in front luggage bay
Lightweight narrow hose set weighing under 4lbs (1.5kg).
Easy Install. Non-damaging bolt-in installation.
Clutter Free. Uses the standard fresh air vents to deliver cool air.
Simple to Use. Control by a single ‘smart button’.
Modern double cage blower with integrated evaporator.
Energy Efficient. Uses less than 1 HP of engine power.
Kits available to fit 911s from 1965 to 1989 (please check for fitment before purchase).