[RMXP] CHANGING PARAMETERS ISSUE

So in RMXP in the Event Commands there is an option for Change Parameters but it only includes MaxHP, MaxSP, STR, DEX, AGI, and INT.
It does not include ATK, PDEF, MDEF, and EVA.
It seems these 4 can only be manipulated through equipment.
But it would be very useful for me to increase and decrease this through another method.
I see that I can kinda mess with these through Status Effects but those are intended to be temporary and its just not a good method for my purposes.
Is there a way to more directly change ATK, PDEF, MDEF, and EVA for a given character?
Or can I at least increase and decrease the stats of a weapon or armor midgame via an event?