How to defend Mongol scout rush?

So far all the ranked games in DE I’ve lost have been against a mongol player who steals one of my boars and then scout rushes me. In each of these games I stole one of his boars to try and even things up, but I always end up getting slammed hard by the scouts he brings in because I don’t have enough Spears in time to fight them off. Is there a better way than just full walling early? I feel like that’d hurt my eco a lot...