jetmech6868, I too had looked into getting bedsides from a 47-52 but ended up with used correct year 46 side panels. The front panel was from a later truck and too wide but I cut it down to fit and looks just fine to me.
There are some on here who just buy 16 gauge sheet steel and have the upper bend made at the steel shop. Matter of fact I just bought a 4x8 sheet for $60, cheap! They then weld on a pipe on top and buy all the uprights to weld on as well. They claim it is much cheaper. Of course the trade off is time and you need a welder.
Check out these two threads and associated pictures.
Here and here
