Possibly a Steyr Hunting 5, or a BSA Goldstar, from memory they are both adjustable in power, but I'm sure others more knowlegablr than I will come along with an opinion. Strictly speaking they are 12ftlb Sporting rifles, not Match rifles, but I have modified my Steyr to accept Diopter Sights and run it at low power. Regarding adjustable power Match Rifles, I believe that they are available but would need modifications to run at 12ftlbs. Possibly the Anschutz 9015 FT or the FWB 800 FT might fit the bill, but only a guess I'm afraid, alternatively, for a cheap gun, the AA MPR might have a power adjuster covering that range, but you'd need to remove the A/T first.
JMHO, Vic Thompson.