The part is a metal roller on a Milgard screen door. See attached rusted picture.
It looks almost identical to the one you sell Product Code: 84-016 except that mine has a hook on the end and yours has a closed loop. Vinyl or metal wheel fine with me. Thanks, Adam
Tom from SWISCO responded:
March 27, 2017
Thanks for posting! The shape of the spring doesn't matter so much. As long as the dimensions of the 84-016 are the same as your roller, I think it could work out great.