Volkswagen Golf needs new engine (from breakers)

Oil and diesel visible on the engine. Suspect auxiliary belt has snapped. Current mechanics looking at it believe it will need a new engine but they don’t do engine replacements. Due to the car’s mileage and trim, it’s probably cheaper to replace the engine with one from a breakers (with similar or less mileage). Absolutely devastated. Anyone know the cost of labour to do this? I’m devastated. It’s a 1.6TDI GT edition with a great spec including electronic panoramic sunroof, which I love. It’s a 16 plate. Or am I better scrapping it? I lost my partner a few years ago and am on my own with 3 kids. Don’t know what to do. Any advice much appreciated.