brexit represents a fault-line that cuts completely across the traditional left/right wing divide. What exacerbates it is that within the Brexit camp there are different views on what brexit actually means. The prime minister says brexit means brexit, which is true, but it doesn't mean anything more than that and therein lies the problem.
You already have two pro-brexit parties: one is called the labour party and the other is called the Conservative party.
I assume you dismiss UKIP for the same reasons I do. That's why I don't see a new pro-Brexit party springing up. There is no political vacuum for it to fill, and neither the tories nor labour would willingly want (for the most part) to be associated with UKIP or anything like it.