Myself and a friend stumbled across this word during convo's on Myspace back in the day say late 2006, It happened due to nuff 'G' talk going down and large swagger about keepin' it real on night's out.
"Carla Pet, tonight we're going to be High Rollin' on that dance floor!'
"Reeg's we're keepin' it real, we're high rollin'!
"Carla Pet, the High Rollin' swagger is going to attract nuff respect!"
"Reeg's we're high rollers!"
"High rollin' is how we roll!"