Want a 451 Duster

I am new to this Forum, but have been a long time resident of FBBO. I have a 69 RR 440 six pack, and want to buy/build a 451 Duster. I put together a 440 Dart back in the 90s, so I have done this type of thing before. But if anyone has one for sale, please message me. In the meantime, I will be learning all I can about Big Block A Bodies, do's and don'ts. Thanks, Gary.