The thinest pistol I have is a Bersa .380--comes in different finishes, all in the $250 to $350 range. Mine has been very reliable and accurate, plus I like the manual safety. SIG 232 is similar size without the safety or slide lock. Of course neither is ever as totally reliable as a revolver, but they give you 8 rounds of .380...
"Adversity does not make a man--it reveals him"