Maybe we’re not talking about the same thing here.

I’ve got two aircraft periscopes and was told that these were from ‘v-bombers’. One of them has a serial number crudely painted on it and when I looked it up it was the serial of a Valiant.

From the posts so far it doesn’t sound like either is from a Vulcan.

You might have a periscope from either XH536 or 537 as they tested Skybolt and had periscopes fitted where the sextant mounts were on a Vulcan.