I wonder why do you want it that small for indoor. Is it supposed to be portable?
No, that's because I've already have an enclosure for this device and want to fit anything inside. It supposed to be autonomous and non-serviceable as much as it can, because I want to drop it in one city and move to another one.
I've decided to build a simple Moxon antenna using glue gun, SAT50 cable, and other small stuff, hah. It works, gain is veeeery puny (because of my crooked hands i think), but it's compact enough and fully protected by casing.