This is a scarce item. It is clearly a Massey Ferguson 50B, identical in construction to #54 but there is no Corgi imprint on the base.
It is also missing Farmer George in the cab.
I have found two versions, this one having a fully orange roof, white wheels and bright metal bucket and no branding. With the Block Construction logo on the roof this would appear to be from a Corgi Gift Set 2 Constructor Set from late in the Corgi era. the set had a 1:36 scale Mazda Pick-up and Cement Mixer, all in the bright orange finish.
The shovel mechanism works better than the official #54, actually staying in position, and the whole model is immaculate.
A similar version, with cream wheels and an black roof but not bearing a Block company transfer, is also available.