@holly43952 Kogan as in Kogan.com? That is a bit like purchasing a battery from ebay or Amazon. There are a lot of honest sellers out there but the battery market is saturated with "counterfeit" batteries. Basically used batteries with a control board that has been reset. It's a definite "buyers beware" marketplace.
We don't usually make recommendations as in where to purchase "stuff" unless the seller is known to the iFixit community. Answers like this can never be objective since everybody may have a different experience. They also lead to a lot of SPAM, which we really do not want :-)
If nothing else I would only by batteries from sellers that actually care for their reputation (ebay and AMazon reputation has a bit of an issue :-) Use a seller that specialize in batteries and call them. See if there are any live people available . Ask them about the batteries and if they offer any kind of warranty etc. You'll be surprised in the difference of stores that actually have employees vs. online only. Just as an FYI your Nokia needs a BL-4CT battery.
Now, in your case we would definitely need to know where (Country only) you are located to see if there are any iFixit "connections".