Replacement Shock Info request

I have a 2005 dodge diesel 2x4 quad cab with 72k miles.

while pulling our 26ft bumper hitch trailer, when I hit a dip in the road I get a few waves up/down of rear of truck,

hitch chains appear to be set right and trailer/truck set level.

so I am thinking I may need new shocks. However truck drives fine, no dipping on rough patch of road.

any suggestions on shocks HD for a 2500 Dodge 2x4 truck.

I looked on Geno's site: bilstein B6, but other info said they were for racing or off road, not good for towing.

local parts house had Rancho rs5279 for F, rs5269 for R
do not know anything about this brand.

these are the only brands I have looked at so far.
do not want truck to ride like a log wagon, just not bounce and roll.

Thanks for any tips.