Grigg, I will keep an eye out for that plate, although to be honest with you there is no trace of a plate like that ever having been on the wheels.
I will have to see how the new studs work out, the old ones {presumed original} are not long enough to allow that plate to be installed and still have the nuts fully on the studs.
I have had little luck the lug nuts {1/2-20, 3/4 wrench sized instead the normal 7/8}, but I did find 1/2-20 flange nuts 7/8 head in a Grade 8.
Been to all the truck parts places, truck tire shops, no luck om finding duplicates.
Since I found one lug nut I had randomly removed to carry along for comparison to be cracked, I figure a nice meaty flange nut of high grade would be preferable to what I have been riding with!