Uli's idea is probably the easiest solution. Another solution would be to buy a 50Hz unit from Japan and get it switched from 110 to 230 volt in Europe (should be relatively easy/cheap) as Japan uses both 50Hz and 60Hz units (depending on which side of the Fuji River you live on).
FWIW, I have asked Accuphase (the company itself in Yokohama, not a foreign distributor) the same question before on behalf of a friend. IF you own it in Japan for more than 6 months, Accuphase will change it themselves at little or no charge, which, if also practiced abroad (and I would see no reason for it not to be), would suggest buying used from a very nice seller willing to jump through an additional hoop for you the buyer.
FWIW, I have asked Accuphase (the company itself in Yokohama, not a foreign distributor) the same question before on behalf of a friend. IF you own it in Japan for more than 6 months, Accuphase will change it themselves at little or no charge, which, if also practiced abroad (and I would see no reason for it not to be), would suggest buying used from a very nice seller willing to jump through an additional hoop for you the buyer.