No.
Your payment must come from one source.
Can you add money to one of the cards to make up the difference?
BTW, while prepaid cards are sometimes valid for use on eBay, they offer much less protection than an actual credit card. Once the money from a prepaid card (or a bank balance or a Paypal balance) is sent, it is gone. PP cannot retrieve it, unlike the 'virtual ' money sent from a credit card.
Also the prepaid cards (and the bank balance) do not have the additional buyer protection of the credit card's 'chargeback' feature.
