Hey Oyvind!

I dont think you will get exatly what want, no matter how much you search.

I think i would do what you wrote in your initial post:

Get some readymade devices:
a232/radiomodul, a 232/USB device and a little hub.

Then you pick YOUR favorite processor - with sufficient I/O's and maybee 2 UART's - could be a Dallas device with flash on it (limited to 16 kb) or some cygnal device. Now you design a nice little PCB for this - if it only handles leds, matrix keyboard etc. That shouldnt be such a big deal. If time is a problem, detailed hardware design/pcb layout etc. could be "outsourced".

God arbejdslyst

Per Guldmann