I don't know of any existing commercial clones that include an integral USB host port, but they may exist.
FTDI do some pretty small USB host controllers with UART/SPI/parallel interfaces that should be Arduino-compatible. It would be possible to design and build your own clone incorporating the controller and port.
Some PCB prototype manufacturing companies publish PCB designs for reuse for a small fee - it's possible that you could find an existing PCB design for a DIY clone that incorporates a USB host interface.