Two Clay Ming Dynasty Burial figures

If these are worth anything point me that way 

I would think more likely Ming Dynasty and the Ming tombs (Shishan Ling) for the origin of these funerary tomb attendants - but are they possibly replicas sold at markets in the vicinity or, if genuine, stolen from the Palace Museum as one would imagine the tombs themselves were heavily guarded and even archeologists have their ways of making sure nothing leaves a site. Certainly they look impressive with their residual orange terracotta and black and red pigment, both valid materials of the time, but I think you need to hand them over physically to a specialist in this field to verify.

Is the material of which the Chinese characters (kanji) are made the same as the base under the vase? It has just struck me the base has a shine to it, which may be white jade in keeping with rest of picture, whereas the characters would lend themselves to being better carved in ivory given the detail required.

Pieces like this really require a physical examination by a specialist , I'd suggest contacting one of the big auction houses like Sothebys or Christies for a referral to one of their specialists.