Tube Recommendation for ARC Ref Phono 2SE

Tube recommendations for the ARC Ref Phono 2SE would be appreciated.  Takes four 6H30 dual triodes, one 6H30 and 6550C. I could order directly from ARC, but that's kinda boring - so wondering what folks would recommend based on their experience.

I replaced the original tubes by 6H30 - DR , and the 6550C by NOS Tungsoll 6550 black plate .marriage in heaven !

Thanks. Googled the 6H30 DR's - ~$300 a piece.  Yipes, but I don't doubt that they sound great.  Any special place you got them?