Entry level mic for 5000a

I recommend the Kenwood MC-60, it is the best all-around base mic I've ever used, and I've tried many Shure/Turner/D104/etc. It you need the mic amp you'll need to wire for radio 8V - I never use the mic-amp. Of course you will need to rewire for a non-Kwood radio or create a cheater-cable, like I do, between the radio and MC60 allowing me to leave the MC-60 wiring pure.
 I have used them MC60's on many of my radios in the past. I have a 5000 but have not yet wired  my spare MC-60 to it. I have even rewired a MC-60 for my FT-767GX (and it took extensive internal rewiring/trace-cut/jump due to the totally opposite FT-PTT method) making it now a dedicated FT MC60 mic. The MC-50 is as good using the same mic but different base/wiring.

I have a Heil Gold Elite (on my IC-9100 and it was used on my old 3000) - it's great (I got a real good 'deal' on it off eBay). The MC60 is near as good but not quite - however, VERY few can tell the difference. 

I had the exact same concerns. Rob, W1AEX, a guru on all things audio SDR recommended the following available for $20 at Amazon. Behringer Ultravoice Xm8500 Dynamic Cardioid Vocal Microphone. I have gotten excellent reports with mine.