Hi Mike Brennan.
Thank you for reaching out here in the Microsoft Community.
You wish to know if the Xbox Gift Card you found is still available.
Please refer to the link below for instructions.
Microsoft and Xbox gift cards - Microsoft Support
How to redeem gift cards and codes | Xbox Support
If you would like more detailed information, please follow the instructions on the right hand side of the page in the previous Xbox link and chat with a support agent via phone or browser, who will be able to provide you with more targeted assistance in this area.
Thank you for your understanding and support.
Best regards,
Zev - MSFT | Microsoft Community Support Specialist