Is there a tube based 5.1 preamp on the market?


Hi All.
I have a friend using a 5 ch. Butler audio tubed amp.
He's using his old Sony rcv as a preamp.
Looking to see it there are any tube 5 ch preamps one the market.
If not,whats the best HT preamp for ~$1000 used.
Thanks,
Dave
david99