I thought the rule was up to TWO G motors (H-impulse) and up to 1500 grams of total rocket weight was considered a "class one rocket" not requiring waivers or HPR certs... that can make a pretty big rocket.
As for sparkies, to my knowledge those are NOT made in anything smaller than a motor requiring a Level 1 HPR cert, to keep them out of the "general public's" hands... (IE kids, though I know more than a few adults I wouldn't trust with them either, HPR cert or no). Sparkies have some pretty specific regulations governing the conditions under which they can be launched (bare ground, minimum distances, etc.) and personally from what I've seen, you BETTER be prepared to fight a wildfire when flying them under most conditions (unless you follow the new requirements to the letter, are flying from bare dirt, on snow, or a frozen lake).
The bigger they are, the more careful you have to be...
Later and good luck! OL JR
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