Ghibli museum tickets from Lawson’s

Hi.
I will be arriving in Osaka on the 22nd October and want to purchase tickets for the Ghibli museum from a Lawson's store.
1) I will be staying in Shinsaibashi; where is the nearest Lawsons to Shinsaibashi station?
2) Going to be staying in Tokyo from 29/10-5/11. If I try to purchase tickets on the day that I arrive in Osaka, what are the chances that there will still be tickets available for any of the dates that I will be in Tokyo?

1) I will be staying in Shinsaibashi; where is the nearest Lawsons to Shinsaibashi station?

Hopefully this link will work for you:-
http://store.lawson.co.jp/#/searcheki/frwd/%E5%BF%83%E6%96%8E%E6%A9%8B/lat/34.6717556/lon/135.5031389

If not, there are plenty around so just ask your hotel if you haven't randomly found one.

2) Going to be staying in Tokyo from 29/10-5/11. If I try to purchase tickets on the day that I arrive in Osaka, what are the chances that there will still be tickets available for any of the dates that I will be in Tokyo?

If you try and go during the week you should be fine. Checking now for next week shows the morning slots full on 3rd, 4th and 5th but the afternoons are ok. The 6th, 7th and 8th are all completely sold out.

You don't mention what country you are from but you can pre-purchase tickets from some JTB agents in certain countries before you leave for Japan too.

Note that Ghibli is closed for maintenance from November 6 through 16 inclusive so I guess there might be some more demand for the few days before they close.

Enjoy your trip!

Thanks for the answers GC3!
I am from Australia but unfortunately it is too late to purchase from JTB as I will be flying overseas tomorrow.
Fingers crossed there will still be tickets available when I arrive at Lawson's.

I think you will be fine. If you have internet access before you get to Japan or once you land you can check which days/slots are free here:-
http://l-tike.com/ghibli/

Click the yellow box on the first page.
Scroll down and you can see the date range for the current month and the next month. Click the orange box next to whichever month you are looking for.
Scroll down and you can see the calendar showing which slots are available on which day.

As is the convention with almost all ticketing systems in Japan:-
X means sold out
�� triangle means limited numbers left (ie almost sold out)
O means tickets available