You will not get something to "drop in and solder a couple wires".

I see the factory amp show up on eBay fairly often. There is one seller that sells a lot of Crossfire parts who will probably be your best bet. Will probably cost you less than $200.

If you get involved with replacing it the one you have, it ripples out to the subs, there are other sensors on the amp that have nothing to do with the stereo, and you will have to pull cable. Of course it's doable - a fair number here have done it.