Help on buying the right replacement battery for Canon SD1000.

Hi,
I got a Canon SD1000 (IXUS 70) camera. However, the camera came without the Lithium Ion Battery. The camera was bought in the US, and while I live in Canada, I cant go back to the store and explain the issue.

The battery that I need is a [B]NB-4L 3.7v 760 mAH Li-Ion [/B]battery.

I have tried to find a replacement battery with the above specs on ebay.
Although I have found many sellers who sell cheap NB-4L 3.7v Canon replacement batteries.
The number of Milliamp hours (mAH) varies from seller to seller. Some batteries are 730
mAH and the number pf mAH varies, while some offer up to 1000 mAH. That is the despite the fact that they might write that it supports my SD1000 model.

In the Canon's original manual, the battery is supposed to have 760 mAH.

My question is this:
Is it safe to buy a replacement battery with the number of mAH being different from the
mAH the original Canon battery (which should have come with my camera ) is uspposed to
have?
Since mAH really signifies the battery's capacity, is it ok to purchase the NB-4L battery
with 1000 mAH, which is higher capacity? Should I try and ind the closes number of mAH to
avoid any damage? I want to go safe since the camera is new and REALLY avoid taking a chance by buying the wrong mAH and hence hurting the camera or having a decrease in performance due to the different than specified mAH. The fact that the original warranty might be voided is acceptable.

Replies are welcomed.
Thanks.