What is the 0.5BTC going to be spent on, exactly? Stock? Advertising? As of right now, there's really only one design available on your store so I'm assuming more designs would also be a cost.
Lenders here love stable altcoins as collateral. If you're hodling any that has a worth around 0.5BTC that would work well with many lenders with the bitcoin to lend.
100% will be spend on creating more more designs for Bitcoin, Ether, Bitcoincash, Litecoin etc. AND marketing the products (Google, FB, articles on crypto forums/blogs).
I hold some Funfair (FUN) but not enough as collateral.