I'm still looking... the simrad NSS 7 has come right down in price, under £700 now. Its a 7" hybrid touch and is sonar ready.
Hybrid means you will need to use it as a touchscreen to plan a route / waypoint etc, but zoom in and out and page selection can be done from the limited keypad.
Its a real shame the 8" version is twice the price
Wilk - I don't have any experience of touch plotter technology on an open RIB, but I do on a yacht and personally feel it wont work for me with wet hands and/or gloves both of which seam a common occurrence on a rib...