Thanks for the input to the thread guys - very interesting, and the ASI advert clearly shows all of the 1990 GAMO pistol range with the 3 variants of the underlever springer pistol.
I had no idea the "Target" was so late being released and this explains fully why we never saw any of them in the Exmouth Club in the seventies.
With three varaints and the late introduction of the Target model, GAMO must have had a very successful production run.
ASI must have done OK at the time as well - we bought our Feinwerkbau Model 65 and 80 pistols from them, and the beginners were buying the Centre pistols so they had both "ends" of the market to feed from for quite a few years!
Rossendale Target Shooting Club. Every Tuesday and Thursday evening 7 - 10pm.