Material spec for hardened Cat washers?

I have a 5U and one of the track rollers is the bellows type. The washer with two holes (6f8280) that is fixed to the roller with two pins has broken. Is there any record of what type material or how hard this metal is? I haven't found any out there for sale and need to fabricate a new one.

Probably just use some 4142HT as is. Part off a piece round on the lathe if you have one.

Original may have been a case hardened steel about to a depth of ~1/16"

I have a roller apart and could get the Rockwell C hardness when I get home tonight.

That would be great. Thanks.

This is for a S or PS Thirty outer roller thrust washer part # S227

Material. 1E320 H.R. steel- pickled & oiled 3/16" thick.

Heat treatment. 1E104. Depth of case .7 - 1.0 mm min. hardness rockwell C-55

So, in at least the case of the Thirties, the washers were case-hardened.

Thanks

Ken