Another option, just for kicks, is to pick up an actual original ST-70 and mod. OT's are wonderful. Put in a Triode Electronics power supply board to start just to be on the safe side and later replace the driver board with the flavor of your choice (I decided to put in a new board but one that used the original 7199 driver circuit in my original Dynaco ST-70). Can put in a new power transformer and tube sockets if you want, tube sockets eventually is a really good idea. Personally, I like refurbishing the old stuff when that is an option though the cost all in is probably about the same as a new kit when all is said and done. Anyway, just a thought.