Hi!
I see you are in Bergen County, NJ. I am in Somerset County. Try Effingers Sporting Goods. For someplace closer to you I think you can go to the national boy scout site and they have a search for dealers near you.
I would push back against the den leader for insisting on the full uniform - it is totally unnecessary and I have never seen a group of tigers in NJ wearing anything other than the Tshirt (and sometimes only the cap!).
If the leader keeps insisting, try to cheat a little - go to Old Navy and buy a pair of navy blue chinos or cargo pants - they will blend right in. There's also no need to buy the "official" belt - at his age, they don't put any achievements on it and it is about 15 dollars alone! Also, buy only the short sleeved shirt, and buy a generic turtleneck of the same color, so the "summer" shirt can be used in winter with the turtleneck layered underneath.
I guess we are lucky in our bear den - all the moms encourage this type of economizing and we've been able to give each other good tips over the years!
good luck!
Jane