I have one of the original Yashica metal hoods made for the Electro 35. It is slightly shorter than the Pentax, and has a slightly narrower diameter. I havn't used it in awhile, but I don't think that it has the rectangular notch that is found on many Olympus hoods to avoid blocking the viewfinder. The way you can tell that it is for the Electro is the diameter, 55mm. The Lynx's used 46mm and 58mm and the Minister's also used 46mm.
A rubber one will usually interfere slightly with the viewfinder, but it only takes of a corner.
Most metal hoods for non-wideangle lenses will not have flare out. They will be straight.
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