1. He can still go without, unless you decide to have him go through some changes.
2. Absolutely! They can build and/or buy and/or have anything made for them, if they have the coin (or anything else to barter with). Otherwise, Artifacts will eventually be available, which can sometimes be weapons. Characters will also be able to request items from their home world from time to time, and they can absolutely stumble upon weapons of any kind as they explore (Aerith, for instance, will soon come across some materia). Concerning the latter, always ask if you aren't sure, though if you keep it reasonable, there shouldn't be any issue!