Thats what i would do if i could afford it. Yes its probably okay to buy used, but try to get it from a reputable seller who has good reviews. You want to make sure they are shipping it in an anti static bag to keep static electricity out during shipping. And make sure they provide a detailed spec sheet so you can be sure your getting the right stick the important specs are, CAS 9 Timing: 9-9-9-24 Speed: 1600mhz Voltage: 1.5volts and DDR3 of course.