judging by the hydraulic set up it's a 300 series massey
as well as lifting potatoes & parsnips , the standen statesman 2 would go slow enough for onions but alot of the drive gears had to be changed over to do it as we used to grow approx 5 acres of 'japanese reds', once we got so behind with the spuds due to bad wether , the boss got in about 25 students to get them out by hand in the blazing sun \ if i remember rightly they were polsih & one of them was called eva wow was she a good looking girl in her daisy dukes & no knickers ...happy days