Gap for another brand vaccine? 1st dose?

Hi Doctor, Please suggest me which specialist I should select while booking appointment? I need to travel abroad and have some problem with vaccine now. I have taken covaxin Vaccine first dose on April 18th in India, after that there are travel guidelines released  with approved vaccine list  from Saudi country, in which covaxin is not the approved one. Only fully vaccinated(approved) person and  no vaccinated persons are  currently allowed to the Saudi country. So I need to travel without taking 2nd dose of covaxin to Saudi as non-immune passanger by not disclosing the covaxin 1st shot but I should take their approved vaccine before August 1st, So, how long should I wait for covaxin 1st shot to lost and take a diffrent approved brand vaccine 1st dose? Saudi approved vaccine list for now: Pfizer johnson and johnson Oxford/AstraZeneca Moderna