They are replacements, not replicas, which is what I assume you are getting at. They are, in my mind at least, not worth the same as those carried originally but as they have been carried (in railway service not just preservation I hope) they are at least genuine. If there were cast and just carried on the Loco during preservation they, in my mind, are worth a lot less. My point being that most collectors, in my experience, want railway items that were carried or used in mainline service. It is for that reason that I didn't ever buy replica pieces but accept that many people cannot , at todays prices, afford originals. I am in the lucky position that most of my collection was bought back in the 1970s to 1990s when prices were reasonable. Even as a student I made regular visits to Corruptors Corner to waste my grant money on railwayana rather than pouring it down the urinal so to speak.