I dont get your example of Cross Contamination as I assume the vegetables you mentioned being cut after the beef are to be used in the stew? Which properly made will simmer at 180 degrees for at least an hour or more
Anyway, as mentioned we will agree to disagree about the use of wooden cutting boards vs. plastic for home/boat use.
I would router the edges of that new cutting board the OP wants to fit to their sink
Sorry for the off topic rant!