The only real "lightduty" WDH for popups are the mini-350, and the Single-Bar 400. I used the Single-Bar 400 for my 2000 Coleman Mesa. But that was 3000 lbs loaded, and 375 lbs loaded TW.
At 3135 empty/shipped, and 4573GVWR, I don't see you saying under 400 lbs TW.
So yeah, a 600 lbs Equil-i-zer would be perfect.
thebrakeman ('70), DW ('71), DD ('99), DD ('01), DD ('05)
2004 Surveyor SV261T (UltraLite Bunkhouse Hybrid)
2006 Mercury Mountaineer V8 AWD Premier
Equal-i-zer WDH (10k), Prodigy Brake Controller