Mass duplicate plugin

I am consistently importing new businesses into my database, however many times I believe I am importing duplicative data. I realize there is a duplicate check when creating a new listing, however I’m looking for something that will allow me to go through my listings in mass, check for duplicates (based on name, address, lat/long and website) and assign whether or not they are duplicates. If they are, I’d also like the ability to merge/delete the two data sets into one.