The only 'orphanage' in the area would be the workhouse. As the nearest workhouse is in Barnstaple, it is unlikely he came from there. Close relatives were often given as visitors, etc. It is likely he would have been classed as a boarder, if he was later paying for his keep.
http://www.workhouses.org.uk/Barnstaple/

Perhaps Charles was a relative of William or Mary Ann Ridmore. Can only guess from the Census, the certificates are the best way to confirm details.

Births Mar 1847 Lee Charles Barnstaple 10 18
Births Jun 1847 MULES Godfrey Charles Barnstaple 10 34
(Possibly reregistered.)
Good luck.