There's no reason why, if you found the right club/school, you couldn't do a JAR PPL and include a few hours on a tailwheel aircraft as part of the whole deal thereby making the total time and cost very similar to NPPL + tailwheel endorsement.
While I most certainly do not agree with the sentiment above that the only reason to get an NPPL is an inability to pass the medical, I don't see any advantage in your particular case in doing the NPPL first.
As always Beagle is correct.