Need a new amp for my 2005 x5 no nav

[jgsx5]

Hi, I have a 05 x5 4.4 no navigation.I bought recently, I knew the amp was bad as the previous owner spilled water from a fish tank and some got into the amp through the wiring connector.I checked the amp and the terminals are corroded and inside the amp the connector and 1st board are corroded and no good. My question is can I but an aftermarket amp cut the wiring connector off and connect to that way, the rest of the radio..the head unit all functions including bluetooth work,just no sound! otherwise I have to find a oem amp. The x5 has a pioneer amp stock. If I have to go oem any help finding one reasonable cost would be helpful,as stated I just got it and used down payment to keep payment low,but I will be cash short for a while . Thanks for any help and I gotta say this is a great site John