I would sell as is. If I were buying a non-working pin of that vintage, I would put in new boards. Heck, even if the pin were working, I would consider the sales price to be "non-working". If the playfield were in excellent condition, I would consider that a plus; I have yet to see an original Bally Playboy with a good OEM playfield.
Oh, I have this tit,el and I have a NOS playfield, NOS plastics, NOS backglass and all new boards. That's $1500 in new stuff right there. I guess if your assessment of the value is accurate, I have a $2500 pin on my hands. I bought originally for $200 in 1989, my first pin.