Perhaps your volumes or your budget can't justify an automatic feed embosser.  Maybe you had an Automark TMI 2000 indenter, and found out that Automark is out of business and you can't get parts, why not take a look at the Numberall 40B.

The Numberall 40B can be used to stamp keys, metal tags and plates such as dog tags, metal labels, and serial number tags.

Weighing only 41 pounds, it is portable enough to be used anywhere.
Characters on Standard Dials (42)
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z c ‘ . – & / 1 2 3 4 5 6 7 8 9 0
Available Character Heights 1/16″, 3/32″, 1/8″, 5/32″, 3/16″
Machine Dimensions 10″ wide x 18″ long x 12″ high
Table Size 6 x 8-1/2″
Weight 41 lbs.
Maximum Plate Size 5 3/4″ wide by unlimited height