I also wear size 13. Having big feet can be good and bad. Ski shops either don't buy many big boots and run out, or they end up having to many and then sell them for dirt cheap. Last year there were some big full tilts on the internet somewhere for under $300. Look around for the sites and shops that bought too many.
Pretty sure I told him to get fitted at a shop and he won't know until then. And if he's truly a size 14 street shoe, I have doubts that he will fit comfortably into a mondo point 29 designed around 12 street shoe. Is it possible? For sure. Plausible in this skiing community, probably not.
i have a size 14, try to wear slim shoes like vans that are mostly canvas, in which i wear a 13. i rode in size 11.5 salomon spks 2 seasons ago ( which left my toes numb and bruised for a while ) but now can fit into size 12 full tilts, which is my current boot.
i do have a pair of Nordica Beast 12's in a size 13.5 i could let go for pretty cheap, theyre in great shape