OPAMP upgrade for Quad 405

uA301ATC is a very old bipolar design, older than a jfet input TL071 as it is a few generations newer but still very old in the opamp world.
What is wrong with using a NE5534A?
BTW I do not know this Quad 405 design so I am speaking in general terms. It does depend on what the part is used for, if it is in the signal path.
I looked at the schematic they have on hifiengine, I think a NE5534 would be something to try. Or even the TL071 as they use in the other version. These are cheap parts to play with.
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Two things to be careful with:

-The op-amp is supplied from resistors and Zener diodes, so it should not draw too much current. (This rules out the TLE2071, because it draws excessive current while clipping to the negative rail.)
-Its input bias current should not be too high because of offset.

By the way, this thread might also be of interest:
Redesigning QUAD-405 DC bias loops