DTG may not be a good option for you because the ink prices cause the per shirt price to be a bit expensive for some. It's hard to say what is "too much" for your particular customer though.
Heritage does DTG printing in Pennsylvania : Heritage Screen Printing, Inc. - Direct to Garment - custom t-shirt printers reviewed at PrinterListings.com
You can find more DTG printers on the east coast here:
Direct to Garment - Find T-Shirt Printers - custom t-shirt printers reviewed at PrinterListings.com