tube power amp for my thiels cs6 speakers

my present system includes cat sl-1 mk 3 preamp,krell ksa-200s power amp thiels cs 6 speakers shunyata orion speaker cables and krell kps 30 i cd player.any suggestions for tube amp under 5k including used ones? i do not listen at very loud levels-75 to 80 dbs sound pressure from my listening chair.

thanks,
rod