[Mumble-bee]

I believe 14 is a tire from a G.I. Joe vehicle. probably the Whirlwind anti-aircraft cannon/trailer or one of the other trailers from c. 1983.

part 15 looks very familiar but I haven't managed to place it.
{{edit: see Thor LP's post}}

#12 actually looks like the battery/power cord cover/door from the back of my old (c. 1979) Panasonic radio, except mine's black, and maybe longer (away from the tabs).

Nothing else rings any bells.