For some of us who might like to help, other non-p/n info (dimensions, etc.) might be useful to post. My own accumulation of parts often came in cardboard boxes, pill bottles, zip-loc bags, tackle boxes, etc.. Way too much work to pair each item to a p/n. But these sort of requests are my favorite way of reducing the accumulation...given enough info.
Alternatively, someone might post a picture of their 258 headlight socket...loose or installed...to help with the search. just a thought.
FWIW...
KD