Arduiono Port expander Options More than 64 I/O

Hi Arduino experts, I have a Mega2560 that I need to expand. I currently have 8 MCP23017 and that is the maximum I can address. I need more I/O. Can I use another 12C device that works in the same way but will not conflict with the 8 MCP23017 Addresses. Is there another I2C device I could use in conjunction with these without any problems. I am avoiding using the SPI bus to do this as it makes code a little more complex and its already scary enough.

Thanks

Add a gate to A0 which can then expand your addresses.
Maybe a 74HCT138
.