alright, let's fucking go.
It is an underdeveloped plane, projected and designed in a hurry, and made mainly from wood. For these reasons alone it goes out the window already.
Is killed by your criteria for suggestions
>can hold minimum 4 pylons for SAM (i think that's what you meant) or bombs.
the Me 262 was never meant to be a bomber, it's a pure interceptor. Otherwise, pretty much comes down to your equipment, as it is designed for use with a jet engine, so remaking it would make redesigning the plane necessary.
no idea, it is concepted as a jet engine plane, but was never even produced, not even a prototype. Can't tell you anything about it.
Now that's something that could work. could. If you weren't limited by your suggestion criteria
>easy to build by untrained personelin cramped conditions.
How much untrained is 'untrained'? are we talking about absolute dumbasses with a grand total of 0 hours in a workshop? Or do the at least have qualifications/knowledge in metal working and mechanics? If not, it doesn't look good for you.
In the end, none of those are easy to build if you limit yourself with an absolute horrid scenario, where you're stuck with literal cleaning staff, in a cave, and on top of it, two of your suggested planes will not even into combat. Even the Bf 109, the absolutely best of the suggested designs, cannot be build without machinery to stamp metal profiles for its construction, and the personnel trained to work said machinery, and then some more personnel to assemble all the other parts, and the final plane.
>can get up to mach 0.8 without structural damage/failure.
Mach 0.8 = 274 m/s = 987 km/h. So, a modern jet plane. Forget it.