Help!! HP Pavilion 500-267C motherboard dead, seeking MB/CPU upgrade compatibility info.

[badmaxx]

My HP 500-267c motherboard is done, and I wish to know which MB/CPU combination(s) I can install in this HP desktop computer (specs in link below) that would be a worthwhile upgrade, given the circumstances. I'd like to stay under $300 for MB/CPU if possible; perhaps an upgrade to i5, and would considered used/refurb as well, unless there's a good reason not to. BTW I believe the original CPU is good, but I think I should be replacing both if I'm replacing/upgrading the motherboard? Apologies, tech illiterate here trying to learn a thing or two.

Thank you all in advance!

HP 500-267c desktop original specs:
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[badmaxx]

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