You don't list the motherboard. If it's only the CPU you are limited by the motherboard socket (see pcpartpicker).
If you want a CPU that your current motherboard doesn't support it will cost a lot as you'd need:
a) CPU
b) Motherboard
c) possibly DDR4 memory (if you have DDR3 now and get a modern CPU)
d) possibly new Windows copy
e) would also have to REINSTALL Windows and all software