This one is a three parter – Disassembly, desoldering and dumping the ROM. The mask ROM is labelled as MPR-15768-T and turned out to be 27C1024 compatible. Which is 1 megabit or 128 kilobyte from what I can gather. First time it has been dumped and released into the wild from what I can tell.
More details can be found at Assembler Games.