Hi kalinux and welcome!
The real Bulgarians (like me) use the BDS standard (as you said "for typewriter"... but that's another story).
This is the one of the best keyboard layouts in the world as confirmed by the world specialists.
But the real story is why didn't you find both the Bulgarian layouts?

Here in LXDE:

You see your stupid "phonetic"?
I could tell you even how to use "phonetic2" layout.
But why? - it seems you know everything, my Bulgarian friend...