It should be fine if its really as cheap as you say.. See if you can test it and check for scratches, wear and tear, etc... If its only 100-200rm difference then its better to get the one with a manufacturer warranty... Usually store warranty is useless as what can they do to repair any damages right?? Still if its from shashinki or kldslr shop then its betters. Thats my humble opinion

Lazada has cashback so just make sure to do your transaction through lazada... Later you can always refund if not mistaken