Might help ya, depending on your point of view. About 25 year ago I picked up a complete Campus green/cream girl with two tone deluxe guard. It ad been sitting in a field rusting for who knows how long. Equally used as your was, I'd say. After an good acid bath, I took the guard to auto paint store and color matched a pint of the green, yet Hardly used the paint. I just used a small brush and carefully placed a thin, so thin, almost transparent coat into the chips. dried and if any built up, lightly, as to not scratch any original paint used a piece of steel wool to blend in. My chain guard looked about like yours with heal and cuff scratches, as well bottoms of step-through. Not exactly chipped but worn and a little regular wear on top of rear fender too. . I didn't use any red lead over any of exposed metal areas, I mean, had I then might as well redo the whole thing and I wasn't what I was going for, nor pristine or 'Restore'. anyway, replenish, might be a better word B/C, then, I thinned out the paint and rubbed a thin coat into it. The color wasn't an exact match but the thin rub-in helped the orig and new blend in, you'd, pretty much, have to know what I did before You'd realize it.
Not exactly a trick for every collector but, my daughter loved the heck out of it fer xmas when she was 18, and all her 'cool' friends too. And still all these years later, rust han't returned and, except I used rattle can on cream fender tips so, a little chipping on edges. , the little rubbed into fender , guard and step through there's no new or returned, rust, chips or scratches. I looks used but no longer abused and not 'patina-ed' (fake).
Moreover the auto paint is thin enough, simi- translucent from thinner, that adds body to old warn paint, it sticks very well over original , and dries hard.