I think you may be getting confused with the initial launch of the gun, the BROWN SAFARI stock was ONLY availible at the 65FPE power output initially, hence the differentiation between it and the HP version and the premium, internally all current guns are the same.
Now you can order any variation of power output and stock combination, i.e. 65FPE in blue laminate, the quoted figures at 65FPE are with the 34g pellet, not the 25g and as ARZROVER says the best speed in the .22 caliber with the 25g RD is slightly below 1000FPS so you have the choice of tuning down a SAFARI model on the HP curve, or tuning UP the HP version on the HP curve (if that makes sense), both require the use of a programmer and someone like Bob who knows what they are doing!
Alternatively you can just get a .30 SAFARI and spare barrels, the .25, .22 & .177 (with slugs) all shoot very well without any reprogramming, the .22 .25g RD comes in at just over 1000FPS on the HP curve and the 25g. 25 at 1000 with the mid power curve, swapping barrels and probe takes less than two minutes
Do you know if it is possible to buy a 22 ART barrel?