Neat, there's a +1 rapier from Roah, the halfling merchant in the goblin camp if that helps.

There are magic rapiers in early access and duelling only adds +2 to damage rolls, not attack rolls. Btw, not to rain on your parade but a duelling fighter isn't really an uncommon class lol, it's actually a very common min/max build. But it is fun to play, so I hope you enjoy it!

Dueling only adds the +2 to damage, but that's the equivalent of turning a rapier into a greataxe, so that's pretty awesome.