I recently submitted an inquiry to Tamiya on the subject and as of yet have not recieved any comment back. So..with the help of Jackhammer81, we did a little comparison of the Tamiya 1/35th Brick Walls and Sandbags to the Tamiya 1/48th.
Upon looking at the sandbags, you can immediately tell that they are diffrent. The two sets look totally diffrent. Not only in size, but also in the way that the sandbags are cast. The 1/48th in my opinion is much more detailed and looks more realistic.
As far as how they compare in scale, each sandbag scales out to about the same measurements and both are slightly over sized compared to what you find in the field by about 3 inches.
The 1/48th brick walls are also diffrent than their bigger counterparts. In my opinion, the 1/35th brick walls have a better look to them with a little better texture. As far as scaled goes, they both appear to be pretty accurate.
In conclusion, Although i have no confirmation from Tamiya that the castings are originals for the 1/48th scale, My common sense and some one on one comparison would definately indicate that these are originals.
