We have a recent budget build suggestion here as well that may be useful to review as that does seem to be in your price range! Full details can be found here: https://community.microcenter.com/discussion/comment/49719
To add onto Ian's suggestion, I would highly recommend visiting your local Micro Center and speaking to one of our Build Your Own associates. They can help you pick out parts and even guide you through some of the other questions you may have when it comes to building it.
I wish you the best of luck! The first build is always the most daunting. Take your time with it, watch lots of YouTube videos, and make sure you spend some time getting the cables nice and organized.
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