Fourees are always a good way to go for those
rarities. I've
had a few
Claudius and
Caligula fourees and they all went for under $500. Fourees also add in the interesting world of
mules, like that Caligula/Caius &
Lucius type pictured above. I've seen some
types of
Caligula denarii sold online that have suffered damage go for sale for under $500, and some of those have decent
obverse portraits.
Of course, for
Claudius, the cistophoroi that now seem to be popping up everywhere and are now cheaper than
denarii. A mere $500 will get you a
Fine cistophorus of
Claudius. Three times the silver, and all the art and skill in the portraiture - you can't go wrong!