JeolEfmo

I'd see if I can find a second hand Dell U2515D or U2719D.
https://rtings.com has very in depth reviews on monitors. The Dells score very high on color accuracy.
https://www.rtings.com/monitor/tests/picture-quality/color-accuracy

Could have a look here: https://www.displayninja.com/best-gaming-monitor-under-250/
 
This is for gaming monitors, but they have other lists, reviews and filters you can use to search for monitors that fit your need.

If you're fine with low or medium aettinga

Early test results suggest the Zen 2 is a remarkably good choice for Photoshop, especially given that an i9-9900 is actually more expensive than an i9-9900K in Australia. https://www.pugetsystems.com/labs/articles/Photoshop-CPU-Roundup-AMD-Ryzen-3-AMD-Threadripper-2-Intel-9th-Gen-Intel-X-series-1529/
 
Adobe products tend to prefer Nvidia gpu. In Photoshop differences are fairly small, but definitely favor RTX, https://www.pugetsystems.com/labs/articles/Photoshop-GPU-Roundup-NVIDIA-SUPER-vs-AMD-RX-5700-XT-1552/. 
 
The system would be well powered with a 450W psu. 
 
PCPartPicker Part List
CPU: AMD Ryzen 7 3700X 3.6 GHz 8-Core Processor  ($515.00 @ Shopping Express) 
Motherboard: Asus TUF GAMING X570-PLUS (WI-FI) ATX AM4 Motherboard  ($359.00 @ IJK) 
Memory: Corsair Vengeance LPX 16 GB (2 x 8 GB) DDR4-3200 Memory  ($129.95 @ Amazon Australia) 
Storage: ADATA XPG SX8200 Pro 1 TB M.2-2280 NVME Solid State Drive  ($225.00 @ Umart) 
Video Card: MSI GeForce RTX 2060 6 GB VENTUS OC Video Card  ($549.00 @ Austin Computers) 
Case: Fractal Design Meshify C ATX Mid Tower Case  ($149.00 @ PCCaseGear) 
Power Supply: Corsair CXM (2015) 450 W 80+ Bronze Certified Semi-modular ATX Power Supply  ($77.00 @ Shopping Express) 
Monitor: Acer XV272U Pbmiiprzx 27.0" 2560x1440 144 Hz Monitor  ($698.00 @ Austin Computers) 
Total: $2701.95
Generated by PCPartPicker 2019-09-12 04:22 AEST+1000

get the vengeance lpx 3200 and tighten the timings(reduce latency)
there's a step-by-step video on tightening ram timings for ryzen 3000, follow this video. it is very easy to do and should not take too much time:
 

Cruical Ballistix Sport LT, If you are willing to oc, I got mine today, it does 4000mhz easy.

Might as well get a decent board, if you do more stuff in the future you could always upgrade to the 16 core CPU on it.

i meant like rx570, 3700 and 16gigs is more than enough tho

This one is 95% of the P3 color space, Can just go on the part picker and search by IPS and higher refresh rates.

https://au.pcpartpicker.com/product/LFRzK8/acer-xv272u-pbmiiprzx-270-2560x1440-144-hz-monitor-xv272u-pbmiiprzx

https://www.displayninja.com/acer-xv272u-review/