I see well for saving on the peripherals. For the monitor you have to ask what do you want?
Full HD 1080P, even higher or less. The higher the resolution you're monitor can go the better games will look but will also be dependant on how much your video card can produce
60Hz, 120Hz, 240Hz? This affects how high the fps can be when V-Sync is on (60fps, 120fps, 240fps) since some games are prone to screen tears and the frequency will also reduce the amount of tears even if V-Sync is off
What size 17" 19" 20" 22"+
If you want to save go LCD not LED
Now for the mouse go for a Razor. Razor mice are made for gamers by gamers they are very precise and quick to respond and will be an asset to your KD ratio
Now for the keyboard I say go for something ergonomic. Gaming keyboards are well and good but many do not come with wrist support and I have found that without it my wrist is killing me after a few hours of play
Send us some links of some of products you are thinking of