Fostering of orphans? Not by itself. What costs it depends on.
If you help say a breeder or owner of a family girl, whom got a very big litter, or where mamma died, you can perhaps even earn some money. They are grateful for help.
the easiest is to contact vets around and tell them you are accesible. Vets usually know of such cases mentioned above, they are in a network for such.
You can also contact shelters around. Shelters too may need fostering mommas.
Such a shelter will usually help you with the direct costs involved too, alike vet costs and extra food, if you are helping them out.
RIP sweet baby. 
