A magnet might help where there is iron but those louvers are pot metal. Many I have seen were pitted badly. The pins that mount them are small as sewing needles and will snap right off.
I discovered long ago that the black plastic louver sections from the later model will interchange.
Best plan in my opinion is buy a later model part and have a go at the DIY chroming paint. I watched a video recently of a guy doing side by side comparisons of 6 to 10 (I forget) different products. Top 3 finishes were so good that only factors remaining were cost and/or availability.