Can Marketpress or any other plugin store and then email to customer a unique code for specific prod

I have a new Multisite using Marketpress and I need a plug in or add on that will allow me to store third party Gift voucher codes and sell them on the site. The way that this should work is the client should have a choice of $10, $25, $50 or $100. After the purchase they should receive an email with a predetermined unique voucher code. This would be exceptionally helpful if I could store the voucher codes in one place and have them accessed by each site that uses this service.
Thanks for any help.