Stereo head unit ,'89 300E

I recently stopped suddenly and sent a cup of coffe into my stereo dash unit. Now the unit is inoperative, shows random characters on the display, and cannot be turned off. Circuit cleaning sprays have not helped. I am assumong the unit has gone south permanently, and I would like to replace the unit (stereo/cassette) with an identical used one or possibly a stereo/cd unit from a similar car that will connect without great trouble.
Anyone who has a working unit for sale, please let me know. Any hints on bringing the original back to life would also be greatly appreciated.


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