Hi Steree
I use Medtronic Enlite sensors with my Veo pump. I would re check the price with Medtronic as the initial set up cost would be more than £100, you need to buy a transmitter as well as the sensors. I think the cost of sensors is roughly £50 per sensor and the maximum time I can get from one is 7 days, the sensor stops at exactly 6 days use but you can re-link it to the transmitter and get a further 22-24 hours from it. The transmitter is quite costly, it is guaranteed for 6 months but mine has so far lasted 3 years.
Medtronic had an offer for a set up kit, transmitter, 5 sensors and charger at a reduced cost earlier this year, it would be worth checking their website occasionally to see if there are any offers.
Definitely ask at your pump clinic to see if they can loan you a CGM for a week to see what you think of it and how it might help you. NHS funding is considered on an individual case basis and is usually for hypo unawareness resulting in a danger to your safety.