What amp would I need?

So i went in and got my speakers changed to Alpine s-s69c since mine blew out(2012 scion tc) and my audio still didn't come back and he told me it was my amp as well that went bad.. Would getting the factory amp fix this issue or should I go with an aftermarket solution? I don't want to spend too much and my previous factory amp ran the front, rear, and subwoofer in the back with no issues. Would the alpine speakers and getting a factory amp again not work out? Or do I have to buy a different amp as they said I need a 5 channel amp to run all 5 of the speakers is that right or would I be able to get away with getting a 1800w 4 channel or 3 channel as I believe my car amp was a 2 channel so what would the difference be? Please let me know quickly as I want to find one to buy and get it installed before I leave town nov 7 and my budget is around 150 max for the amp and this was the factory amp in my scion OEM Pioneer Audio Amplifier 86280-21030

Also they said If I upgrade from my factory amp I would have to rewire the car for around 100$ does that seem accurate or are they just trying to gouge more money from me?