Yes, you can buy a new LCD and a new digitizer assembly but then you run the risk of not installing it properly or even straight. The LCD by itself comes with a layer of adhesive and once it's stuck, it's not coming off without ruining the LCD. If it's not perfect it won't fit on the phone and just wasted the money.
Trust me when I say this, spend the money on the assembly and do it the right way. You will not be able to remove the LCD from your phone without destroying it.