...That's about max for a FUNCTIONING B90...Your best bet is to make your own...Do a search in Batteries, and there's a bunch of info.
I'm using a 3000MAH homemeade stick in a 9AN...works great, but needs a seperate charging facility; i.e. the stock SF charger will not completely recharge the pack.
A good compromise is using 2400MAH batteries, which should charge o.k. in a stock SF charger.
--dan