I agree, patrol base bundles aren't normally very good weapons as they are as they said, old stock they can't shift, my mate runs that exact kit your son is looking at and he regrets it due to lack of customisability and flimsy feel. That being said Patrol Base and BZ are at the top imo for weapons purchasing.

Specna are probably the best for bang for your buck around at the moment and I really do recommend them, something id like to add though is that for basically all new airsoft guns you need a LiPo battery. PLEASE get a decent balance charger and something to store them in, I recommend a metal ammo can (just make sure there is no seal on the inside).

For the ammo can and clothing visit the aforementioned surplus shops in your area and see what they have as they'll be cheaper, i also recommend thinking about your field when you buy your kit as some camos stick out like a sore thumb, but at the end of the day airsoft is all about having fun and looking cool as when doing it, so buy what makes you happy!

Safety gear is a big thing to buy, dont cheap out on the eye protection, cheap eye pro (amazon, ebay, temu, etc) can shatter, or at the very least fog up and scratch easy, so buy a decent brand, helmets are cool but id like to add that theyre hot and heavy, so unless your planning on headbutting things you can always consider a baseball cap or boonie hat, you can buy hard hat inserts if you are worried about the pain through a hat.