I don't think you can without a credit card on file. You can use the Paypal debit bar to pay for the AT subscription, but the debit bar requires a credit card and a positive balance. When the subscription was new, a member was taking Paypal and giving out webcertificates a while back to pay for the subscription, but I don't remember who or if they're still doing that.
Good luck, ,the subscription is well worth the price.