We have a 319.
They take the 206-13 needles. DO NOT use regular 15x1 needles as that can cause serious damage to the bobbin case.
They use special bobbins.
They have built in cams and also use the Singer flat cams.
They are oil hogs just like the 401s and 500s.
They are noisy due to all the moving parts, but this does not affect the sewing of the machine.
They are VERY good machines.
They ARE NOT industrial strength, but are stronger than most domestic machines.
Needles and bobbins can be had from Sew-Classic and other places. Get your needles now as they are becoming harder and harder to find.
Joe