I would suggest calling Graco to make sure they made one for it. They will need the model number and possibly serial number located on the seat. You can E-mail them or call them.
Contact Us Graco
Not knowing which particular model of the bassinet you have got, it is hard to suggest how to clean the fabric.
Please see if your model is listed in the list of bassinets on this site. Download the instructions and check the section on cleaning and maintenance.
Product Instructions