Joe,

The Caesar's and the MGM are really common so you're doing good at $10 or less.
I have no idea about the Flamingo. Haven't seen it before so I can't be the judge of that but Bill Judge would know. Or Pam. Pam knows sooo much.

Shipping? Lots of bubble wrap and peanuts in a Priority Box with a couple of prayers thrown in.

I'd check e-Bay for sold prices on the Flamingo. It looks cool but.

Also check the Ashtray Project,
http://www.nevadacasinoashtrays.org/