currency questions

I am taking with me to Japan 50,000 yen in 50 and 100 yen coins. Where can I change these into notes? at the post office? or do I have to go to a bank. Will a bank do this if I am not a customer?
Are the old grey 500 yen coins in circulation still? I have a lot of them. Also I have some 500 yen notes. will a shop accept them?
Also I would like some absolutely crispy untouched banknotes including the 2000yen as souvenirs. Where can I get these? Is there government or central bank in Tokyo I can get some from? thankyou all

You can get new notes from banks.
In Japan if you use more than 20 coins of the same kind to buy something they can refuse to sell it to you.
I think you can bring your 50k yen in coins to the bank to get it changed, but I suspect there might be a fee of some kind imposed because of the large number of coins you have.. The old 500 yen coins are still legal tender, but they are kind of rare, you might wanna keep some of the coins that are in good condition.

A search tells me that 500 yen notes were replaced by coins in 1982, so even if they are still legal tender I doubt you will find any merchants that will accept them.

- It depends on the bank, but if you take "a lot" of coins to a bank teller to change them into bills, some charge a fee for large quantity, for example, over 50 coins.

- 500 yen notes: you can hang onto one for a souvenir (they don't issue those any more), and the rest you can try to use at shops with cashier (no vending machine); real young people might not even know those, but it is legal tender.

- The same with old 500 yen coins; vending machines don't take them, but staff should accept them. If you think you might be using vending machines a lot (for example for ticket vending machines), you might want to take the lot to a bank and ask to have them replaced.

- New notes including 2000 yen notes: you should be able to get them at a bank or at a post office.

It really depends on the bank. My bank requires an account, and the money is deposited into the account. I brought in about 500 1 yen coins (500yen). Of course you have a heck of a lot more, your pockets must be heavy @_@.

thanks people for your help. I still am wondering though if the post office would be more helpul? perhaps they are not as profit motive as banks and so would change coins for no charge?