Hi Chris, I don’t really like the look of bulb horns on racing and sporting vintage bikes, so I go minimalist just to comply with the law, and buy a cheapo cycle horn, spray it black, and fix a recessed ring bezel on the end, with a fine mesh fly/wasp/bee excluder Araldited into the bezel. It looks suitably vintage and costs very little. Make sure that paint doesn’t get into the reed, or it will never work again ! Genuine ‘period’ bulb horns are usually full of dents, and fetch silly prices these days, as I’m sure you have discovered on Fleabay…
Brian
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