SteveH
I am not sure what your question or need for more heat sink resistors. I know you can buy heat sink resistors that have built in heat sinks to supposedly keep them in their heat range. The resistors in you picture appear to have heat sink fins on them and if they are running over their heat range you may need to install ones with a higher wattage. I have such a resistor to install in a vintage stereo Sansui 9090db receiver that is known have this resistor fail but have not gotten around to installing it after over 15 years! I do not put many hours on this one, usually just Christmas time.
I have added extra heat sink to a hot running power transistor in another receiver that had too small heat sink area originally. I used heat sink from junk computers and JB Welded and bolted the extra heat sink to the existing heat sink. JB Weld has steel filings as the filler and will conduct heat forever without failing with age like the HS greases. I do not know how efficient it is at conducting heat but would be much better than regular epoxy. I also added a cooling fan as this heat problem had turned the printed circuit power board a dark brown.
Charlie
