Fonsecas are very good mild smokes
The Griffins is also a very good mild smoke (expensive, though)

RP Connecticut is a very tasty mild smoke, but may border on medium
Rolys (Puros Indios 2nds) are mild-med and dirt cheap

Hemmingways might be pushing the envelope a little, but might be worth a try.

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And listen to what BPP says. He knows is stuff.