try these - they do the PPPoA ADSL modem part, but out of the box, with no other config, you set the Mikrotik pppoe-client to authenticate the customer. So even if the ISP is PPPoA, the modem converts the PPPoE to PPPoA and back again. No NAT, no 'half bridge tricks', just a modem
So if it gets damaged by lightning, you throw it in the rubbish and plug in a new one. No config. Even customer can do this. Easy. All config is in your RB.
We use these because in Guernsey there is only one ISP (C&W) and they do not support PPPoE on their ADSL, only PPPoA. In UK, ISP supports both. But with these modems, we don't care.