The vintage Sansui, Marantz, Kenwood and Pioneer can have outstanding tuner sections in them. For 500 you can get a very nice one and send it to someone like Radio X and have it gone over. This is far better than buying most new ones in my opinion. Just using a Pioneer SX 780 in my second system I'm still amazed at how good it sounds. It's used mainly for our local NPR station.
RECIEVER recommendations
I am in the market for a used reciever (2 channel) for a second system. I can spend up to $1200-1500. My speakers will be Nautilus 805's. They need 75-100 watts of power. I also like to listen to low power college stations, so FM sensitivity is a consideration. Any recommendations?