For the cost of shipping they are otherwise free. Treads came off the aft swim and fold down ladder of a 1989 60'MY.
There were made two seasons ago and only oiled. Didn't want the maintenance so I had Starboard treads made instead.

5 treads-15 3/4" X 4 1/4"
6 (1 top 1 bottom for fold down) 4 1/2" X 2 3/8"

I'll also supply the screws and binding post for the fold down ladder but at a later date. Treads are with me in FL and screws are in WI. Can't seem to upload the photo so PM me and I'll send them directly to you.