So you're posting in the Gen2 (2004-2009) Prius forum but your profile indicates you have a Gen3 Prius (2010-2015). So you might be posting in the wrong forum... There's alot of different relays in a car and looks like Amazon does sell a "relay integration unit" for 2010 Prius... But in general relays rarely fail and it's almost always the signal that tells the relay to work that's not working. Here at Priuschat we go through a process to properly diagnose what's wrong based on symptoms then we find a way to confirm that what you spend your money on is going to work and won't be a waste of time. So not really sure what you're trying to do here. Only advice I can offer is that you can bring some tools to a wrecking yard and find the relay unit you need and practice pulling it out before you have to work on your own car.
On a gen3 it is a white module with relays in the engine fuse box. It has two tabs on each end to allow it to lift up. There are cables with connectors on the bottom that usually have enough slack to disconnect but the cables will be stiff. I would make darn sure a given relay inside was bad before attempting replacement. From a customer's 2011 at a local independent hybrid shop. A 2010 has a different part number Bottom view from ebay part
They are real pain in the butt to change too very carefully..get car inside wer can be hot . Take a heat gun set on 225 and go around the box bottom area get wires very warm . The unit will pull up almost 2 inches . As you pull it up give the plugs a shot of heat they slide off mo better. I hate these things