I suggest you to purchase a domain name and redirect your blog to that address let it have any extension .com or .net or .in. Whatver may be the redireciton at the backend no way your blog will be afffected either on indiblogger or in search rankings.
It may be possible that your search rankings may go down due to this blogspot.in or blogspot.com redirections.
Domain names can be purchased at very cheap price from bigrock for INR 200 or from Google domains itself which cost USD10 or USD12 based on extension. Also integration with blogspot blogs is easy.