Tony I reused my original spring and got Nick to run me up a couple of guides and power bands, much nicer now but as you don't have a spring, I'll have a look through my spring collection and see if any of them fit the original metal spring guide and you can have that and Nick can make you a guide set up to match that, I thought I had a Welsh Willy tuning kit for a SS but it didn't fit in the end (you could have had that otherwise), I may have a spare barrel latch spring somewhere in one of my spares boxes, leave it with me and I'll have a look in the shed during the week and if I've got one I'll send it to you (I can't see why they are not available anymore as considering they are used in god knows how many different BSA break barrels).
Pete