There is not, as far as we know, any du’a for finding a good spouse that has been reported from the Prophet (peace and blessings of Allah be upon him), but you can pray to Allah to bless you with a righteous spouse.

There is no sin in asking someone to make Du`a for you whom you hope will have his Du`a answered, provided that this does not involve anything prohibited. However, it is better and more appropriate not to ask.