http://search.ancestry.ca/iexec?htx=View&r=5543&dbid...1861 Census, we can see Richard Armitage sr with Mary his wife and the children you have.
The problem with the non-catholic people is they don't give parents names in the register.
I have the following informations :
Francis Armitage married Sarah Black, 1874-12-24, Clarendon, Anglican. He's from Onslow, she comes from Bristol
James Armitage married Mary Ann Young, 1887-03-31, Bristol-Eardly-Onslow, Anglican. He's from Onslow, she comes from Bristol.
John Armitage married Eliza Jane Armitage, 1872-06-15, Clarendon, Anglican. They are both from Onslow.
Annie Armitage married Samuel Sunstrum 1881-10-06, Eardley Anglican. They both come from Onslow.
Isabella Armitage married Thomas Major, 1879-10-23, Eardley Anglican. He's from Bristol, she comes from Onslow.
No parent, no witness mentionned. It would be nice to see the register in case the parents or witnesses signed it.
Richard your grand-father, I believe you should know who he married ? you have the date ?
Ref. for these mariages, BMS SGO
Did you check other census ? this is your best way to follow the family.
Jacynthe