Hi, I would like to replace the 13T cog on my Dahon Curve D3 with a 16T one. This bike has a SRAM Spectro T3 Internal Geared Hub. Will any of these two cogs fit?

http://jensonusa.com/store/product/C...ette+Cogs.aspx

http://jensonusa.com/store/product/C...nglespeed.aspx

Any recommendations on tools?

Thanks in advance.