either Ryzen 5 1500x or the Intel i5 7600k is sufficient.
I'd also upgrade the GPU to AMD Radeon 570 ;)
get an i5 7600k if you aren't going to upgrade for a while
If you have only 200 euros, there isn't really much that you can do. If you are on an AM3+ board then you are pretty much stumped. I guess you could get the CPU I'm using, FX-8350, but your board may not support the wattage that it requires and it isn't really that big an upgrade (I can't keep stable 250+ fps, but in 5v5 I rarely go less than 144fps, and if I do, it's Cache T-spawn).
You are much better off just saving your money and getting a Ryzen board and processor when you have enough. Buying a new CPU for that board would be a very poor investment, as it would barely get anywhere near to what you want and that wouldn't last long for when you want to play other games, or Valve decides that everyone is getting too much fps and takes some of it away in the form of a feature that nobody wants or a map revamp.
7700K clocked up to 5.0ghz
dude i5 2500k cheap and strong
250+fps
144hz monitors are just 60hz monitors but they cost more cause they want more money and you think "i have 144hz monitor i can see enemy better now!" it doesnt work like that... You can buy 30hz monitor and play with 30fps it looks same like playing 300fps and 144hz.
For you fx8350 or smth like that, else goto am4 socket and r7
7600k with somewhat decent cooling & OC and you'll be alright for the next years unless volvo pushes another truly useful update which will drain the fps by 40%. 7700k if you don't mind spending a bit more $. But even when the 7700k has a higher base clock, eventually you'll end up having a lower OC cause it usually runs hotter than the 7600k.
E: Didn't see your budget. 7600k if the 200€ is for CPU only. But you'll need a MOBO and DDR4 as well. If it's 200 for all parts, either save up or get some used old gen i5/i7.