Hi Phil,
Thank you for the kind comments. The B3 is an unusual airgun that is no longer in production, so it's probably at that transitional phase between a discontinued item and collectable. Now is the time to find them, hopefully for not too much money. I saw one advertised in the current issue of Airgun World for £100. It is certainly a pleasant rifle to shoot after Jon worked his magic.
I'd be very interested in seeing some images of your Perfecta and if at all possible, a scan of the instruction booklet at your convenience.
Kind regards,
John