If you look at 600s and 650s you'll find more options. Get a secondhand bike because you will drop it and dropping a new bike brings heartache, and in 2 or 3 years you will want to move on and get something else.
When putting your shortlist together, get insurance quotes, as inurance can be costly for your first year.
As for training, I went to Ian Biederman who used to run his own business in Royston. Now he's the chief trainer at BMW Rider Training, still in Royston. My wife tried them but got on better with Bike Sense who used to run courses out of Bourne Airfield. They're still in the same area. The biggest outfit in the area are Camrider, who seem to do a decent job.