Technically, the 8700K will push higher FPS most games. Whether that matters depends on a number of factors. When we have a G-sync or Freesync monitor, we no longer have a hard minimum FPS we're trying to shoot for (like say, 144FPS to achieve v-sync on the 144hz display), anything from 90-144FPS+ all winds up looking pretty good at that point since it is all synchronized, so the differences between a 2700X and 8700K are less of a problem.

The 8700K is better for maximizing raw gaming performance. If highest FPS possible is the goal, stick with the 8700K. On the other hand, the arrangement of execution resources in the 2700X makes it very suitable for running other simultaneous compute intensive workloads, like software based H.264 encoding with good quality while gaming (Streaming).

If we overclock the 8700K to 5GHZ+, then the multi-threaded advantages of the 2700X largely vanish, and the 2700X can't really be overclocked so keep that in mind.

Get the best performance you can afford in budget without compromising the rest of the build.

If it's only a bit of streaming then I'd say get an 8700K, but just make sure you have proper cooling for it. I used an MA620P for a while with a 200W TDP and my temps stayed around 75-80 degrees with occasional spikes of up to 90. A dark rock 4 pro or R1 universal should be good enough. 2700x will net you fewer frames overall when you're not streaming and tbh it's not entirely necessary unless you plan on multitasking frequently on it. The 2600X nets 10% less frames than the 2700X yet it's 50% cheaper. I would personally go with the 8700k (that's actually what I have so there ya go), but the 2600X isn't a bad option either.

2700X will not bottleneck, I think.

Well, a i7-9700K (Canada prices) will cost you more than a i7-8700K, if anything of the below is for real.

https://postimg.cc/image/un9whtda3/

A R2700X would also be a good idea.

I use an I7-8700K and a 1080 with a 1400p 144hz G-Sync monitor (Dell S2716DG) and unless games are really pushing the CPU, my CPU rarely reaches 50% usage. Only a few rare games leverages the CPU properly (Dragon Age : Inquisition and Mass Effect Andromeda are a good example).

Unless you aim for a monitor that displays 200+ frames, I would actually recommend the 8600K unless you need the extra threads for several applications running and/or streaming/recording your gameplay.

I am also from Canada so I feel your pain regarding prices.