If they are simple straight metal rods, longer ones (3', for cutting
to length you want), as small as 1/8" diameter (maybe smaller) can be
purchased at Lowes or Home Depot.

Or purchase a thin metal strip, drill holes for your present rods, and
attach to the drawers.

Or drill the holes a touch larger, fill with dowels and re-drill the
holes for your rods.

Has the drawer sides bowed outward? .... I'm supposing not, but check,
anyway!

Sonny