11 x 7 APC should get you in the high 13,000's

If you use a tuned pipe easily in the 14,000 range with that prop.

With a tuned pipe you can also go with 12-8 and tune the pipe length so that it lowers the RPM down to the 11 -12,000 range as if it were a long stroke 61.

Your choice.

Here's an article from Don Lowes RCM Magazine column were he discusses tests he did comparing a 61FSR (61VF has same specs) vs a long stroke OS 61 SF.

The OS 90 carb he is talking about in the article is the 7D carb with the larger diameter insert. You could chose three different throttle bore sizes on the 7D carb. There where 2 brass inserts that could be installed in the carb's rotor.

The large insert 8.5mm bore was designed for the 61FSR engine so that you would get enough vacuum to draw fuel with out a punp or pressure system installed.

The smaller insert 9.5mm and the no insert 10.5mm options were to get better top end out of the engine but required pump to get the engine to idle as the larger bore didn't provide enough vacuum draw for fuel at ldle. By the time Don Lowes article appeared in RCM mag OS had introduced the 90 FSR which include the 7D carb but with minis the brass insert. See the last 2 pics of the 7D/7DV card manual for the specifics of the carb inserts.