good tube preamp match for classe ca300 amp

am in process of upgrading system . i now have vtl 2.5. preamp . because of budget i need to buy used. what tube preamp would mate well with my classe amp. other components are classe cdp100 cd player. current speakers are psb stratus gold. my plan is to upgrade speakers last-am thinking b&w 803d. i love the sound of the vtl preamps, but they are hard to find used. there are alot of both conrad johnson and audio research(ls 25 mk11) preamps on audiogon . i would hope to buy used under $3000. thanks for any advice.