http://www.bestbuy.ca/en-CA/product/seagate-seagate-backup-plus-slim-2tb-2-5-portable-external-hard-drive-stdr2000100-black-stdr2000100/10281963.aspx
Seagate Backup Plus Slim is a great external hard drive. I linked the model I have. It's 2TB but also comes in 1TB, 3TB, 4TB. Works really well with my system. It's currently on sale at Best Buy.