You can use either a forwarding service where you order yourself to an address with a personal code, or a proxy buying service which does the ordering for you.

The big forwarding service would be Tenso: https://www.tenso.com/en

Proxy services include

Buyee - https://buyee.jp/ (though they don't like VPN access)

Noppin - https://noppin.com/

Japan Rabbit - https://japanrabbit.com/

amongst many others.