The cheapest useable, reliable and feature rich china made 384 resolution thermal scope and monocular combo that you won't need to upgrade after purchase will run you $3,300 new, with a 5 year warranty.
Buying anything cheaper is like throwing money down the drain.
My suggestion is to buy the monocular first and then the scope.
You can PM for the details so this thread won't wander off from Mus hunting.
SJC