The #6 grind is not available on the 7" Model #4. Sorry: If it were available it would definately be a chargeable option and it would count towards your 5. The Randall shop will not forge just one or two blades. They usually forge 50 or more at a time.
At this particular time, being as they are 5 yrs. behind...and 13 weeks behind on shipping schedule, this knife and option will not be offered. I hope I made that "clear" and not "murky".
Best, Capt. Chris