nathanbush,
I got my 6,000# Dexter axle's custom made for my application for about $320 each, they are torsion, however I had them made to sit taller, the bottom of my trailer is 19" off the ground. I'll never use the spring axles again, with the torsion axle there's no maintenance, except grease, or oil bath if you chose. Also they Make zero noise when hittin' bumps of drivin' down a dirt road.
Later, Rob