You'd have to trade out of SBD into something else. You'll need ETH to buy direct and I am unsure if any markets are available for BTC to EOS..

You could trade SBD for BTC, then BTC to ETH, then ETH to EOS ..

Or, use https://blocktrades.us/ for an SBD to ETH trade, then buy EOS on Kracken or another open market...