Netherlands NBDS 31/NS 3500 class driving wheels.

6′ 8″ diam., 18 oval spokes, rect inner rim, 4¼″ apparent tread.
Hub 14 ½″ face dia., 2″ out from the tyre, pin in line at 11″.

Sources: Works drawings.

Casting: 63.5 mm tread dia., 56.6 i/d., hub 1.6 mm out from the tyre, pin at 8.73 mm.

Casting prices and stock . Netherlands loco sets, price list

Scan of a casting in a set for a NBDS 31 / NS 3500 class

Note: the works drawing of the drivers shows the inner face of the hub recessed almost to the level of the backs of the spokes. To achieve this effect in the model you must remove most of the machining allowance from the back of the hub - it will provide space for extra wide axle bearings.