I had done the following research before I got your response re: the dates, and I used today and tomorrow's dates for departure and 10 days later for return, so you can adjust it as needed:
with departure date as today and return date in 10 days (5/28/09), since I didn't yet know the actual days of travel, needed. Price may vary according to the actual dates.
United Airways has the only non-stop flight for about $200 and the travel time is reasonable. (scroll down a bit on the page to this airline)
Roundtrip train travel with Amtrak is about the same price ($200); each trip would be approx. 14½ hours. Train would leave from South Portsmouth, OH and arrive Philly, PA
Greyhound $165 (refundable ticket--non-refundable: $148) approx. 15 hour trip with one transfer
Departing: May 19, 2009
From: Chillicothe, OH
To: XXXXX XXXXX
Returning: May 29, 2009 (Philly, PA)
I understand you want to keep it under $200, but the travel by plane seems the best choice, re: accessibility and time.
It was difficult to find the closest bus and train stations to Mantua, besides Philly.
Also, be aware that certain discounts may be offered for students, senior citizens, etc., so inquire about this.
You can call Greyhound and Amtrak to get more specific info, which may help you:
Fare and schedule information
If you need immediate attention concerning a reservation, call a service representative at 1-800-USA-RAIL (1-800-872-7245)
I hope this info was of help to you and wish you much good luck with the trip.