Bob, the engine is coming apart as we speak - a complete teardown. The bottom of most the cylinder liners have been mushroomed out by the broken rods (red arrows) so it will take some time to get them out without damaging the case.
The rotating assembly is scrap, badly damaged. If I have it straight, the output spline damage shown would have been from the engine trying to stop the Sexton dead when it locked up.
The case may be OK. We'll check it with dye penetrant when apart.
I take your point about carefully checking we are buying usable parts.
Are the very thin, closely-spaced steel cylinder fins as-cast? If so, they are very high quality castings. Spin casting maybe?
Malcolm