Yeah , I`m actually thinking of someone like Steve Pope or someone experienced at this sort of thing. I shot it today with the 21" barrel and its very accurate , if just a bit on the unwieldy and scarry side. I don`t think its the original barrel unless it came off a US market gun (also its 18.8 mm dia).
Makes a great benchrest springer due to it being recoiless, by the way its .177. Could do with a re-blue after any work.
Cheers Don , I`ll give him a call.