Your location is the USSR most of us are not familiar with what is available there.
Start here
http://www.tomshardware.com/reviews/best-pc-builds,4390.html but sub a GTX1050 preferably the ti for the video card. You'll need a copy of windows as well say $120 with the downloaded version from newegg.com.
The really insane budget solution would be a refurbished Dell mini tower
Dell OptiPlex 9020
(i5-4570) for $249
It comes with an AMD card that has directx 11. Realistically you may want to switch the video card to a GTX 1050 which might require upgrading the power supply. Look up tomsdardware on how to do this, you need a power cable adapter. Win 7 can still be upgrdaded for free to win 10, just google it or PM me.
They also have monitors such as the
Dell E Series 19" (E1913) for $49.
;
Note the AMD card draws 35 watts the GTX 1050 75 watts.
An alternative would be one of their workstations Dell Precision T3610 is floating around for $460 this evening, again that would need a new video card but the power supply is sufficient, a low profile GTX 1050 should work. the xeon processor is roughly an i7 and it comes with 8 gigs of memory which is always nice to have.
Cheerio John