I’m in the middle of a classic rookie mistake. I have added to many LEDs, to a prop. But now i’m stubborn and trying to make it work. I guess it’s from these fool's quests we are learning.

I have added a 4 meter neopixel LED strip to a festival totem. Now I run into the problem of a battery. So I have 240 pixels X 20 mA (minimum) = 4.8 amps, is this right? 4.8 amps min. and max 14 amps seems high?
I'm struggling to find batteries that can deliver this. I have found some airsoft gun batteries that delivered the amps, but they are 11Volts. and the LED strpis are only 3-5 Volts, can I use a dc to dc converter, and use the batteries? Or how do I go about this?