Why not tackle the root cause of the problem which is probably drainage? Moss will return year after year if your lawn has poor drainage no matter how much spreadables you throw at it!

Rather than buying machinery to do this once - twice yearly task, I would be more inclined towards finding a decent landscaper to do it for you.

see Find a landscaper, gardener or designer by county - Landscape and Horticulture Association - find a trade to find someone local to you.

Alternatively if you still feel like buying your own equipment then I can highly recommend Agri-Fab Spreaders.

see Agri-Fab Garden Products - Lawnmower World

Hope this helps solve your springy lawn one way or another!