I'm sure you can get a 360 cheaper , 1972 340 has a cast crank and 9.5:1 compression , I think , edit , early 72 had forged crank , later in the year changed to cast , check it out , if forged crank go for 340 . great price
http://www.allpar.com/mopar/mopar340.html
http://www.ehow.com/list_7239270_mopar-340-engine-specs.html