Small bolt pattern wheels on a 70 340 Dart?
14x4.5 or 14x 5.5 steel wheels will fit fine.
Typically they are refered to as J wheels as there is J in the stampings in the wheel.
In 67 the stampings are inside the wheel where it can not be seen with a wheel on
68 or there abouts the stampings are on the outside around the valve stem.