When I did mine I used a 36 Ton Kobelco track machine. No good hitting it with anything lighter. I was lucky from the point of view of having access to this type of plant, hiring it in will cost approx £150/£190 per hour, but it will get the job done. Levelling can be done with the laser on the outer jib, no problem.
You should be able to get a quote locally from any good contractor that does farm work, many here in Ireland.
Rolling a grass strip with a heavy roller is a disaster, you compact the upper layer of soil and wreck the natural drainage. Slit draining with pea gravel will help any drainage issues but a good collector drain/sheugh is needed first.
Can PM details if required.
Jon