Just a suggestion, but I just had ten baffled flasks made by our
glassblower. It took him about 10 minutes to put the "dents" into the
Erlenmeyer flasks we brought down. So these can be made in-house for a
tiny fraction of the commercial price. Obviously, this only works if
you have a glassblower close by, but most chemistry departments have a
staff person who does glass repairs, fabrications, etc.