RedTag Camera through eBay has the popular Sigma 17-50mm f/2.8 lens with optical stabilization available for $240 (for Nikon) or $250 (for Canon) after applying coupon code PRESDAY.
Canon:
https://www.ebay.com/itm/Sigma-17…33c9190962
Nikon:
https://www.ebay.com/itm/Sigma-17…33c6a4131f