This is exactly the kind of advice I needed.   I think I'll put the public addresses in a CSV and test a small batch using electrum. 

This whole process will be done no more than 6 times (200 sent once, and then 100 sends five more times). I'm making some physical bitcoins.

I was able to use the link above to calculate a very inexpensive send if I'm willing to wait 48 blocks for confirmation or 8 hours, (which I am): Total cost estimate: $2.30

I'm not a coder/scripter so making a cool "time saving" workflow probably would take a long time. :-)

Thank you all!