Harman Kardon TA5000x pre-amp tubes

I had a scratchy sound that I deduced was the 12AU7 in my pre-amp section (discovered by the near-source soldering iron test) .  I had an old one that I expect is weak (i have reasons) but works; it fixed the scratch.  I m considering changing out the full set of pre-amp tubes (4x 12 AX7, 1x 12AU7) and I'm willing to spend about $20 per tubes.  I was looking at some of the less aggressive Groove Tubes and would like some advice.  Is this worth doing for the $100 or so I'm willing to spend and are Groove Tubes a good pick?