Not available options: Disabled or hidden?

I have a form with these elements:

• A checkbox
• A dropdown with a list of options

It is an eCommerce site which uses points as currency. During checkout user has the following options: The checkbox allows user to pay the order with a credit card instead of the site points, and the dropdown allows user to select delivery method (Standard, Expedited, In Store Pickup, etc.) All the delivery methods are available if user pays with points, however when user check the option pay with credit card, some of the options are not available.

What should be the best from a UX perspective? Display the non available options but show them as disabled? Or simply do not show the options in the dropdown? Or is there a better solution?