The cheapest is to translate the stamps yourself, get it reviewed by a friend, then go with your friend to a notary office to get the document notarized.
1- Photocopy all the pages that have stamps in your passport. 2- Prepare a document stating each stamp that needs translation. Make a simple format that states page number, where the stamp from, and on which date. 3- do that for all stamps that are not in English or French, even stamps prior to your residence in Canada.
The notary office will probably add a cover letter stating their info and the info of your friend (as a translator). They will both stamp and sign each page of the document.
It’s much cheaper than get it translated by a registered translator and it’s certainly acceptable by cic.
@graphicalmanx do note that you are not allowed to have translations done by a family member ("parent, guardian, sibling, spouse, grandparent, child, aunt, uncle, niece, nephew or first cousin").
Interestingly enough the documents I can find do not forbid doing the translation yourself. Even so, I'd be hesitant to do the translation myself, considering they do not want people close to you to translate your documents (and that exclusion holds even if your family member is a certified translator).
You are allowed to have the translation done by a friend, but they must then provide an affidavit, as
@wilkan points out ("An affidavit is a document on which the translator has sworn, in the presence of a commissioner authorized to
administer oaths in the place where the affidavit is sworn, that the contents of the translation are a true translation and
representation of the contents of the original document.").
If you have the translation done by a certified translator no affidavit is needed.
(Quotes come from
https://www.canada.ca/en/immigration-refugees-citizenship/corporate/publications-manuals/operational-bulletins-manuals/canadian-citizenship/admininistration/general-file-processing/applications-translation-documents.html ; there is similar information available in the
Help Centre)