Just my 2 penneth worth.
The rear wheel with holes in it is Dennis. Same as fitted to their trailer pumps.
The front wheels are simply 23 inch rim Sankey wheels, as fitted to a lot of vintage lorrys. 33x5's as you note (33 (OD) - (2x5 (height) = 23 rim) And they are 8 stud, not 6. There is an adaptor between the 6 stud hub, and 8 stud wheel. If it were mine, Id put the adaptor between the wheel and the hub, not in front of the adaptor. It would look more accurate in wheel terms, but it would bring them further out, may have wing issues.