Go buy a gallon of Xylene (117 octane) and pour it in.
That on top on the 87 in there will bump it to around 89-90 octane.
Even a couple bottles of the largest & best octane booster is not going to get you much more than one full point of octane.
It will probably still ping, but if you stay off the throttle it should not hurt the engine.
The PCM can only pull out so much timing though.
