If you can overclock to 4.8-5ghz then your CPU still has some life for maybe 2 more years because ddr4 is quite expensive right now due to the manufacturers price fixing dram. You can go this route.

Keep
CPU, Ram, Mobo, SSD, HDD, PSU

Change to
GTX 1070/ 1070 ti /  1080 - 1690 /1989/ 2246 lelong various vendors

or if you seriously want to upgrade then here is an option

Keep
SSD, HDD, PSU

Change to
Ryzen 2600 - 800
Team Elite 8gb 2400hz ddr4 x2 - 295x2 =590
Asrock B350m Pro4 -299
GTX 1060 6gb - 1131
(Overclock for better results)
Total: 3025 lelong various vendors

Intel solution
i5 8400 - 695
Asrock B360m Pro4 - 323
(You can't overclock the processor and it has only 6 cores than the Ryzen. You would however get slightly better gaming perfomance if you fight stock intel vs stock AMD)
Total: 2944 lelong various vendors
Intel solution

CPU: i5 8100 - 445
Mobo: Asrock B360m-ITX/ac - 419
Ram: Team Elite 8gb 2400hz ddr4 - 295
HDD: WD 1tb Blue - 150
GPU: Zotac 1050 ti - 689
Case: Elite 110a - 150 (You can opt for an Silverstone SG13 - 180 which is smaller and has better airflow due to the mesh front)

You have 2 power supply options that you can consider. An ATX power supply which takes up more space in the case and blocks ventilations or go for an SFX power supply that would let some air vent into the case through the adapter. A

Here is a recommendation for a SFX PSU: Silverstone SFX 450W Bronze - 285. It has a fan that won't break down after long use (ball bearing fan is good. A sleeve bearing fan would break down and make noise after long use).

Total: 2433 lelong various vendors