Which acoustics to choose?

Question

Acustic systems

Greetings. Your help is very much needed. Essence of the question:
There are 20,000 rubles. You need to buy speakers with this money and connect a microphone to them. This is necessary for a kindergarten in a not very large room. Ideally - 5.1 computer acoustics with a microphone port, but I did not find any. Buying an amplifier and acoustics with a mixer is not an option, because. expensive.
Advise a system with 5-6 speakers and a microphone up to 20,000, or at least an implementation scheme.
PS dvd-karaoke is not needed.