I can offer the following Opamps that will work in the EE Minimax Dac as well as other equipment. All can plug into a dip socket.
U1/U2 Position Dual Opamps
2x OPA627AU on Browndog adapters (soldered by Cimarron/Browndog) $85
2x AD797BR - each unit has 2 797BR singles on a dual adapter $25
U6/U7 Position Single Opamps
2x Burson Discreet (matched pair) DIP's shipped in original tube $85
2x OPA 627BP $50
All opamps are in good working order. They have been burned in through use in my Minimax DAC and are ready for plug and play. All prices include CONUS shipping in anti electrostatic packaging.