This is the standard feature set.
When you boot the CSS, if it does ask you for a license, enter the number you have received.
If you did not receive a number and bought the S11K-500ST-7.5 license, send an email with your proof of purchase and the serial number of your css to licensing@cisco.com.
If the CSS does not ask you anything, then you're good. The standard feature set is the default.
Gilles.