Just wire a dynamic mic if you have one. I got sick of wiring new mics, so I wired everything as 4 pin Cobras, and got adapter connectors. Saved me a ton of time resoldering. The HR-2510 was a great local rag chew radio, and a 10M DX radio. Now is the prefect time for them. Better than any Magnum or Ranger crap. Not much power, though.
Yep, they are both great 10 Meters radios for the price! I have been hearing lots of them on 10 Meters lately. Rewiring mikes can be annoying, so it might be easier for him to just replace the mike element.