
If it's for scanning canine pregnancy (and not sheep) you could always try www.caninescan.co.uk in Boston, some 30miles from Grantham if this helps? Prices on the website and they do come to you for a small additional price.
I do know of a sheep scanner (farmer) near Lincoln, but for the life of me, I can't remember the name of the farm or his address (I have 'silver surfers' disease ha ha).
I could take you there no prob as I can drive the route in my head, but I have since moved to the North West otherwise I would have happily driven and got his details for you (wasn't far from where I lived).
Edited to say: Just found his details although they may have changed. I have lived in North West for 5 years. Glebe Farm, West Barkwith on the A157 : Tel:01673 858919. Good luck!