Popular Hip Hop/Rap Choices- Rode N1TA, Samson G-Track (USB) and any of the SE mics available.
I have alot of friends who do Hip Hop so I know! The best quality ive heard of hip hop from these mics comes from the RODE N1TA and any of the SE series mics. I'm just buying a new one myself and I'm going for a SE mic due to personal recommendations from other music.
But as many will tell you on this forum..some mics work for people some don't..it depends on your voice and style too. And theres no 'perfect' mic for Hip Hop/Rap recordings as theres a number of things that can affect recording but theres obviously mics that are popular and these are the ones. You can get some of them on eBay but if you do and its cheap ask the seller a question and if it is a genuine model and howthey can verify this otherwise youll end up with a crappy chinese mic that isn't anything like the real thing.