Ouch. Been there, done that.
If it were me, I'd just go ahead and get G rated tires if your rims can handle it. G614s are the ultimate in my opinion but for about the amount of a name brand set of E rated tires, you can grab a set if Sailuns.
But again, a lot depends on the capacity of your wheel.
There is a guy near me selling four H-rated Westlakes on 17.5" wheels for $1200.
2015 F350 6.7L Lariat CC LB
2016 Vengeance Touring Edition 40D12
Former Forest River Campers:
2004 Puma 30FQSS
2010 Sabre 31QBDS
2014 Work & Play 30WRS