you would be better off going with spending no more than 120 dollars on keyboard and no more than 30-50 on mouse and use the rest for gpu/cpu/monitor. you can also ask for a custom system build recommendation on here and we will get you the best bang for your buck. just specify with the keyboard if you want mechanical or not and which switch types you prefer if any.
just to give you an idea
PCPartPicker part list:
http://pcpartpicker.com/p/38P1k
Price breakdown by merchant: http://pcpartpicker.com/p/38P1k/by_merchant/
Benchmarks: http://pcpartpicker.com/p/38P1k/benchmarks/
CPU: Intel Core i5-4670K 3.4GHz Quad-Core Processor ($209.99 @ Amazon)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler ($30.99 @ SuperBiiz)
Motherboard: MSI Z87-G45 Gaming ATX LGA1150 Motherboard ($156.98 @ SuperBiiz)
Memory: G.Skill Ripjaws Series 8GB (2 x 4GB) DDR3-1600 Memory ($79.99 @ Newegg)
Storage: Crucial M500 120GB 2.5" Solid State Disk ($69.99 @ Amazon)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($64.99 @ Newegg)
Video Card: EVGA GeForce GTX 780 3GB Video Card ($549.99 @ Amazon)
Case: NZXT Phantom 530 (Black) ATX Full Tower Case ($109.99 @ NCIX US)
Power Supply: XFX 650W 80+ Bronze Certified ATX Power Supply ($69.99 @ TigerDirect)
Optical Drive: LG WH14NS40 Blu-Ray/DVD/CD Writer ($59.99 @ Microcenter)
Operating System: Microsoft Windows 7 Home Premium SP1 (OEM) (64-bit) ($84.99 @ NCIX US)
Monitor: Asus VX279Q 60Hz 27.0" Monitor ($279.99 @ Amazon)
Total: $1752.87
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-03-12 19:52 EDT-0400)
this setup leaves you 250 dollars for a good keyboard/mouse/headset
you can also save money on the monitor, this is a ips 27" or the case but just to give you an idea how much you should spend in each component to get the most bang for your buck