30-400 USD or so
380 auto. Many good brands of ammo out there.
Less than $100. Probably looking in the $50 - $80 range.
Try want ads, gun shows, gun shops.
Russian made
100-1000 depending on exactly what you want/have.
2mm in case length.
You don't define what "better" means to you. Price? Size?
You can purchase a new gun for around 380 dollars. Your gun is worth about 250 dollars in the used market.
$75-$125, depending on model and condition.
Best left to a gunsmith
25-75 USD