Per request of a customer, I talked to Jim about this the other day and here's what I got, in quotes where appropriate. He said that this was "changed about 7 years ago" to the TL783, and that most problems occurred "when the transformer was tapped for 200V" and also indicated that the transformer putting out 200V was rare. He also stated that it was a straight pin for pin swap with no changes needed to be made otherwise. I do not have in stock at this moment and have some coming in, but if you need this part to make your P/S more reliable, I will gladly send you one at no charge, even if you didn't buy it from me at Big Daddy Enterprises. Just drop me an email with your address. US only though, overseas will do for the cost of postage.