EngOnAPlane

Chargeback on code 4846 (page A-14 or PDF page 419 http://www.mastercard.com/us/merchan..._CB_Manual.pdf) cardholder states he was not given opportunity to choose the desired currency (add "through willful disregard of cardholder instructions by merchant"), ask your card issuer for a dispute form. If they don't give you a dispute form then ask your bank regulator to force your issuer to do it.

As for the proprietress's attitude, I'll do my damndest to make the issuer follow through and squeeze the pips out of her (i.e. not settle out of issuer's pocket). Australian merchants can impose surcharges and require minimum spending with notice and consent, but nowhere in the RBA override of MC's rules did RBA void a foreign cardholder's right to be billed in AUD.