gordons gasstation in the dessert - medical supplies and melee weapons -unguarded
sanfran (not in the tanker) - guns and ammo (there is also a FLC

CH1 chars love this place.) -let´s say it´s "guarded"
adytum- all kinds of leatherarmors, guns and ammo -guarded
ncr. dusty and rawside saloon- guns and ammo, melee weapons and medical supplies -let´s say it´s "guarded"
gecko - guns and ammo, medical suplies and melee weapons -unguarded
new reno - guns and ammo, melee weapons and medical suplies -absolutly unguarded
edit: also the only known hospital for CH1 is in the ncr.you shouldn´t sell melee weapons or medical suplies (drugs included) to a gunshop. lower prices.
same for guns. dont sell it to a medical/melee shop. nuff said.