Sorry to hear you had such a bad experience. Losing money to a scam is frustrating enough, but not getting any useful support afterward makes it even worse. Marketplaces really need strong systems to protect buyers and sellers, because a few bad users can damage the reputation of the whole community.
As for the rude message you received, unfortunately online platforms always seem to attract people who hide behind a keyboard. If you’re selling honestly and providing accurate descriptions, one person’s insults shouldn’t define your reputation.
It would be nice to see RacingJunk improve their fraud reporting process and do more to handle abusive users. A better community depends on both the platform and members holding people accountable. Hopefully your future experiences are better than these last two.