All rungs are 1-1/4" diameter by .065" wall thickness. (Standard Rung), unless your section width is wider than 24". In this case, you probably have heavy rungs - 1-1/4" diameter by .105 wall thickness.
Rung Replacement: It is the recommendation from the factory that all rungs be replaced when any rung shows signs of worn/smooth serration's or if any rung is dented, worn through or damaged in any manner. For a statement from the factory, click here.
All replacement rungs are supplied 24" - standard .065 wall.
To remove any welded rung from the rail or plate, you must use a rung reamer tool.
There is no need to replace the rung plates unless they are damaged.