I just found (and tested) a good substitute for Bobo's RF LED's batteries, American version batteries, or easier to find.
I went to the local Walmart and took the wrap of the original Bobo's batteries and compare. The size is not exactly the same (Bobo's batteries are more thicker), but it works perfectly.
Look for the ENERGIZER brand, lithium, number 2032. They fit perfect, easier to take off/install. I bought a two-pack for about $2.50 and that will be good for back-up purpose at Dragon*Con.
Bobafettish was asking earlier for this, so I guess this will be a good search for all Bobo's lights owners here.