Hi Richard,
It is indeed a White, ..a Road Commander II to be precise. (Does look a little Mack F700 ish when viewed side on)
They were imported & on sale in the late 70s early 80s from White Truck Consessionaires, part of the Fleet-Hire Group based at Coleshill near Birmingham. (Rylands, who I worked for after de-mob, were part of the same group)
They were imported without front brakes & had to be upgraded with add on kits at Coleshill in order to be type approved & road legal. Fabulous spec vehicles for their day, although they did have a habit of catching fire due to very poor wiring.
Cheers........H