Glock question for Glock experts

[bellavite1]

So here's the plan:
I want to get a Glock 23, with a 9mm and a 357 conversion, as a nomatterwhat kind of gun.
It would become my edc (hence the 23 vs 22) and the two conversion barrels would ride in my bdu wallet at all times, kind of survivalist thing, if you will.
My budget is around $500.
I am looking for the most cost effective way to do so.
From my research it appears that Gen 4 has more caliber-specific recoil springs, and I stand a better chance of running 9 mm without having to switch the recoil springs with a Gen 3.
What is your experience?
Also, what is your recommendation for conversion barrels?
I heard not so stellar reviews of the Storm Lake ones, better with the Lone Wolf ones (again, my budget is limited).
I am aware of potential reliability issues if I don't use 9mm mags and ejector, but if I have to bring them with me all the time it kind of defies the purpose...
So, what is the best compromise between cost,. reliability and feasibility ?