China business visa documents

Respected sir,

this is athar "Manager Operation of our company, sir, i want to visit china regarding to purchase a machinery from china, so, as per your requirements you needs "Original invitation or confirmation letter (used to be called Visa Notice) from an authorized government organization like the local foreign affairs office in China;"

but our invitee told us last time came some clients from Pakistan.
They just ask for the invitation of our company which then approved by China Council for the Promotion of International Trade,"

so, please guide us that should it be acceptable/sufficient by your esteemed embassy to get the visa.

Anticipating for your early reply please.

best regards,
athar