Firstly, there's US oz and Imperial oz which are measurements of volume while ounce is a measure of weight.
Assuming they meant US oz,
There are 957 US oz in 1 cubic ft.
Set up the dimensional analysis as follows so the units cancel in the numerator and denominators leaving $ as the final unit.
$350 x 957 US oz x 1ft = $334,950.00
US oz 1 ft 1
Assuming they meant it as a measurement of weight (now we will have to use density),
There are 28 g in 1 ounce and
28,300 ml in 1 cubic foot.
$350 x 1 ounce x 19.3 g x 28300 ml x 1 ft = $6,827,375.00
ounce 28 g ml 1 ft 1
All the best!