No offence but this topic is kinda a lil pointless due to the fact you could have PMed a guide or a friend.
But since I'm replying I might as well help.. You can get a V4 from any good toy shop such as Toys 'R' Us' etc etc.. The price depends on a few things but on average its usaully around $20-$30 or below $20 depends on where you go.. And the best place to go? I dont no where you live or what shops are in you local area so yeah have a look around..