Your client is a man between the age of 18 and 55.
Your client may have been enrolled in the draft, which would provide another form of ID. You can verify whether your client was enrolled in the draft by going to www.sss.gov/
On this webpage, click "check registration". It will ask for your client's last name, social security number, and date of birth. Enter the CAPTCHA numbers and letters to prove you're human, then click "submit". If you client has a Selective Service record, there will be a link that reads "Print Letter". Click this link, and print the letter. If your client has no Selective Service record, you will get a message that says "no record found".
Were you able to print a Selective Service letter for your client?