So are you saying the orange/brown Victoria is scarce?
Well, 51-100 examples recorded...yes.
How that translates to $ is another thing,
to the dedicated Postmark collector, the desire would be strong to have that amongst the collection, but value really unknown $3 - $20 perhaps, but that is a guess.
"Duplex" means 2 of anything, postmark has 2 parts, the "killer" and the date and location part.