Highly unlikely, there used to be a chip that would turn a standard
dram into dual port, went up to 1Mbyte IIRC. At least 10 years ago so
probably long obsolete.
This is being done quite a lot on graphic cards, where the graphic chipset
itself (or in some cases a programmable gate array), is used to provide
such access. The problem of course is that most DDR memories are 'burst'
orientated devices, so the external buffer needs to be large enough to
support a full burst. Also the complexity is very different for a
sequential burst orientated read access (as needed on a video card),
versus a generic read. A lot will depend on what speeds are needed, and
the nature of the expected I/O. Some video DRAM's, offer the ability to
have two pages (or more) open at once, to simulate dual port operations.
Cypress do an interconnect family, to allow dual port access on a variety
of memories. A search for 'FullFlex' devices, may provide what is needed.
Best Wishes