Do you mean Impact airguns? RAW is in the US and if it was something Ben did after the sale of Theoben ,Then neither Impact or RAW would have had any dealing'swith it as its not a Theoben type rifle the OP has . Or I may be wrong
From the OP
I have an early Fac btas fx cyclone that has served me well for many years.
Would chambers sell it? https://www.gunspares.co.uk/products/24846/CYCLONE/ part number CS781