need use cryptonight-hevy algo (this algo not present to nicehash), and price coin is up for example, the same Haven (XVH), use cryptonight-hevy. or use cryptonight ultraheavy algo (example, IPBC)
stock.excange or tradeogre.com - they perfectly work with cryptonight an algorithm and the output to the exchange of a new coin is quite simple. Why not to add a coin on any of them?