Both the Edwyn Collins gear article and the Colorsound fuzz write-up appeared in the same issue. Really love that one, couldn't put it away for a long time.
The Barnes & Mullins Champion Fuzz in question is an orange coloured, 'thin case', three knobs in a column pedal. It first appeared at the time that Solasound changed its name to Colorsound around 1970 and introduced the silver cased version with the orange lash graphics. Internally, there was no change to the Solasound Mk IV and V Tonebenders.
According to the article, the first version of the Solasound Tonebender, with two Mullard OC75 germanium trannies, was introduced in September 1965. It was designed by Gary Hurst, who had initaially worked with Dick Denny of Vox, but took his ideas with him when he was approached by the Macari brothers who had coined the name Solasound.
The next development, the MkII Professional, used three OC75's or OC81 transistors. It was at this time that the first Vox-badged surfaced. Solasound also made a MkII for Marshall, the Supa Fuzz.
The Macaris kept changing the case design until the last Solasound one, the Mk V, a yellow case with three knobs in a triangular arrangement, flash fuzz graphics with a large arrow underneath the switch which says, HIT IT!
BTW, the Supa Tonebenders, with a different circuit, appeared in 1973 while the third version, the Jumbo Tonebender came in the late 70's.