Apparantly you must know more about what is on the web. So go find
what you need.

The ONLY service manuals for Canon I have seen on Ebay are for old
printers and the like. How old is the BJC3000 and similar? You might
be able to get a hold of one in 3 or so years after Canon decides it is
no longer cost effective to provide support for the printer.

I have pages of links of available on the web service manuals.
Only no recent Canon manuals at all.

Of the regulars here, I do not know of any that are Canon printer
products authorized.

You might try in a computer repair forum, as it looks like of all the
Canon printer authorized servicers within 400 miles of me, a total of
10, they all are listed as computer sales/repair shops, not electronics
repair.