Yes, you can run them like that especailly if they are not next to
each other.

Any good saw shop can replace them. Price varies widely. $2.50 to $8
is probably a pretty good range.

Saw teeth whether new or replacement, should never come off whole and
should be very hard to break. The technology is there.

You might take them to a good shop and have them check them out for
flatness or you can do it yourself.

See: http://www.carbideprocessors.com/pag...aw-Blades.html

Tom