340 Timing / CAM Issue

Those look like stock non-performance springs. I'd replace those - that's probably why the cam died. Stick a set of Comp 901-16s on it.
I also would think the best case is find a replacement engine. That one - that's a huge tossed together pile of sh_t. Hopefully your "buy it and try it" approach at least leaves you parts you can reuse on the next one.
To the guy you bought it from - don't quit your day job - you really should not be allowed near an engine again and you owe the buyer some $$ back.