http://www.worldwidedx.com/general-...-mosfet-conversions-upd858-mb8719-boards.html
Yup.
While you can still get the bipolar transistors that are used on these chassis, they are scarce, and go for a lot of money per piece. The Mitsubishi 2SC1969 and the NEC 2SC1307's are no longer being made, and while there are a lot of them out on Ebay and in electronic stores, they are mostly fakes. Getting genuine 2SC1969's and 2SC1307's are going to cost you anywhere from $13 to $20 apiece. MOSFETS usually cost about $1 to $1.50 apiece. Do the weigh-in. Personally, I'd rather do the conversions, and be able to replace them with a cheaper part than try to sniff out an original final, and pay the money.
Yup.