Is bcom(a&f) of ignou valid for courses like cpa, cfa and mba from outside india?

Yes, the BCom (a&f) with ignou would be valid to take up CPA, MBA, etc. Such a bachelor's degree gives you the relevant subject credits required in order to appear for the exam and further to attain the license (of course on combining it with other degrees to meet the total credit requirements) in case of CPA exams. For MBA, the bachelor's degree, plus any of the entrance exams for MBA (like CAT) will fetch you a seat.