You might be actually looking for a "manriki". It's more of a chain weapon or flail than the club-like mace. In fact, there is no shaft to it at all. Despite how easy Gogo makes it appear, a weapon such as she uses is difficult to weild and you would need a highly competant teacher to learn it (and a first aid kit). Gogo Yubari also had a blade inside the ball of her weapon that pops out at will. That is probably customized. I am sure there are places on the internet where you can buy one to complete a costume for cosplay, if that is what you wish, or for your own amusement. A search engine could point you in the right direction if you phrase your search correctly.
Google Directory Cosplay
http://www.google.com/Top/Arts/Animation/Anime/Fandom/Cosplay/
Anime Costume resources:
http://anime.about.com/od/cosplay/tp/aa12.htm
I believe it's a morning star mace!
eBay is your best bet, or you could have a costume commissioned. There are many experienced cosplay seamstresses champing at the bit to take commissions, and a Gogo Yubari costume would be simple enough that the cost wouldn't be too high.
Gogo Inc. (GOGO) had its IPO in 2013.
The country code and area code of Yubari- Hokkaido, Japan is 81, (0)1235.
As of July 2014, the market cap for Gogo Inc. (GOGO) is $1,434,725,125.89.
The symbol for Gogo Inc. in NASDAQ is: GOGO.
The country code and area code of Yubari District- Hokkaido, Japan is 81, (0)1237.
Gogo Garifallou's birth name is Gogo Garoufallou.
gogo 4 is named okari
mosh is number 1 gogo.
John Gogo was born in 1932.
Gogo Nushi died in 1970.