Hi Ian55,
Overall things aren't that bad, I will say that the cutter sprocket is well on it's way to requiring replacement but believe me we've seen much worse here on the ODK forum.
As far as the rear roller chain being lose is concerned, that can be easily sorted out by adjusting the flat steel bar with the slots in it which mounts the land roll clutch to the chassis side plate. There are two planes of adjustment, up and down and also left and right. The vertical height is adjusted by the lower nut and bolt that is visible at the lower area of the land roll clutch sprocket while the lateral adjustment is done with the other nut and bolt at the upper area of that flat bar. It will take a bit of trial and error for the non experienced but after you loosen the bolts you'll soon get the idea of how it has to be done using the combination of both adjustments.
Eventually you'll have to replace the cutter sprocket, chain and also the top sprocket on the transfer shaft. But for now I can still see you getting a fair bit more usage out of it if it is correctly adjusted and not too tightly.
Cheers,
BB
