Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
Given that what you are asking about may be a Sentry Safe, may I refer you to Sentry Safe Customer Support? they would be most likely to know the part number and the cost of the part, if it is available.
They are here:
At a guess, you are asking about the battery holder for a Sentry Safe, but I cannot myself find a part # ***** it nor any vendor to sell it. So going to Sentry Safes themselves seems the next step to try.