It depends where you get them, what condition they are in, if they have any work done to them, and how willing the seller is to part with them. I had the chance of getting a free set of 081's about a year ago but the seller was too lazy to ship them to me (on my bill too). I have also priced 081's with bowl and runner work, larger valves, and springs good to .510 lift for about $450. The average junk yard price that I have come up with is around $80 to $150 for a set. That being an as is set that they pull off the motor before you arrive. 081's are becoming slim pickens and I have been on the hunt for a long time. I am getting a free set of 416's so I decided to go that route instead. I couldn't justify $500 on heads for a motor that I am not keeping. | 
