heeeelp please audio reserch 5SE - resistor blew up

I have a tube tester at home and source my NOS Tung Sol from probably the most reputable guy on planet with awesome test gear Andy at Vintage tube
... your results may vary

IF you can’t hear the difference a NOS Tung Sol make in the power supply of a REF5se you need to upgrade your system, your hearing or both
stop by Seattle and we can swap in 4 nice NOS or the factory tube see how ya do......

enjoy the music.....

I also trust Andy to test NOS regulators and rectifiers. Using Tung Sol in two Audio Note components. T-S recommended by the designer.

But let’s ignore all that and focus on REF 5se or any other tube preamp above let’s say $10 K

invest in a spare set of tubes, Factory if you desire
and a decent tube tester

both of which pale in comparison to your initial investment.....

and DHL services most of the planet, why not get that 6550 tested or replaced before installation?

Yea some people can hear the difference in regulator tubes.  I can't and you need not show me.  We are all here to try to help the OP revive his line stage.  I have had it repairing gear that's been "NOSed" by snake oil merchants.  Audio Research, Sonic Frontiers, you name it.  But too many people just get talked back into it after and after a month or two they call me again.