The cost implications would be quite high i would imagine even if you found a vet willing to carry out the procedure , and if you did find a vet i would be worried about the morality of carying out an unecasary op on a healthy dog . Firstly there would be a consultation fee then anaesthetic fee, then an x ray to locate it , then the operation fee , and costs for any other meds needed as a follow up for infection controll , then another fee for removal of stitches , i would imagine this cost would run into hundreds of pounds as it isnt a medical reason insurers would not cover this type of op as it would be voluntary such as speying or neutering . Also there are risks associated with anesthetic and recovery as with any proceedure that requires sedation , a full anesthetic would be needed due to the need for x rays and the simple need for the dog to be perfectly still .
In my opinion ( and i know you didnt ask for it but your gonna get it anyway ) i would leave well alone its not doing any harm the chances of it doing so are millions to one , and the benefits simply out weigh any mumbo jumbo about not wanting it tagged on the inside , this of course is your dog to do with as you see fit , but as we are gifted with the pleasure of caring for our four legged friends its our duty to thenm to make the right choices for them also , and i think removing a micro chip is rediculous due to your belife that it no longer serves a purpose . sorry to sound opinionated but if it touches a nerve it was meant to .

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