$40 to 50, depending on how I feel.
Just remember insurance is for you, not the buyer--so it's whatever you are comfortable with being out if something goes wrong. The buyer is covered by Paypal.
My sketch collection: http://sketchcollectors.com/gallery.php?user_id=727
I'm offloading my sports cards for cheap. Check out MonkeyLots in a B/S/T forum near you!