I can't speak authoritively, but I don't see why not. However they'd best be a VERY good friend. You'd have to give him your AS ID and password (same as for eBay). Then he can log on as you to do the transaction.
What you are doing is allowing him (her) control of your AS and eBay accounts.
It really is best to get a credit card of your own and keep control of things yourself.
I can answer that as I'm off to the bank shortly to get a money order to pay for some stuff I got from a vendor who doesn't accept PayPal or Credit cards. There are sellers out there firmly entrenched in the 19th century. VBG.
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