Advice for Transmuter/Cleric

[svwilson]

One more thing: self-buffing spells.

Maybe I can use Polymorph in this regard. Can anyone suggest a creature I can turn into which:

1) Has hands and a mouth for spellcasting
2) Has a CON and DEX higher than 16, to improve my saving throws
3) Has no more than 12 HD?

Some natural armor or flying ability would be good, too