HT1 replacement battery

[Hawaii-Mike]

A friend asked me for help with his Yamaha HT1 - a bike that I know little about.  The electrical system is 6 volt. The battery is dead.  The Yuasa replacement is 6N2-2A.  Does anyone know of an AGM or alarm-type battery in 6 volts that works for an HT1?  The battery is small and it fits in a tight space.  An even slightly larger battery won't fit in the stock location.

Thanks, Mike

[m in sc]

I run a 6v alarm battery in my c2tr,  it's tiny. just hit lowes or home depot.  I got 7 years out of the last one

[Hawaii-Mike]

Thanks Mark!