Best bang for the buck battery backup - eviltoast

Like the title implies, I’m trying to figure out where to pickup cheap used or new battery backups (ups) in Canada.

I have a couple of small servers I run, so around 1000+ watts should be good.

If I have to replace the battery inside, that’s not a problem, there is a battery place inside my city that offered cheap replacements for around $30.

Any suggestions help!