I get all my frogs from UE.
I'll let you contact UE for prices on the imitators and variabilis.
I know the imitators are more then the highland variabilis and if you look at them they are very very similar looking frogs. We can spot differences of course but very similar.
Mark and Elaine would be able to tell you which is more bold, but don't get over worried about that, it's all about how your viv is set up, and time to adapt.
I just got borja ridge vents from them and people say vents are shy, they are bold as can be for me, male is always out and calling and you have the 2 females following him
Contact UE, see the prices for both and boldness.
They may not have one or the other available right away but they will surely be able to help you.
I'm very happy with their service