If you do want to pursue the keep-and-repair option, and you have space at home, then the most painless way could be...
- buy a written off car with a known good engine, have it delivered to your house
- find a good mobile mechanic to fit the new engine (probably with 'box) , they are usually a lot cheaper per hour than a mechanic with premises
- sell the remaining written off car on ebay, buyer collects. You can include your old engine & 'box in the sale, bearing in mind the block and ancillaries can still be salvaged.