Marantz 2226 as a pre-amp.

I have a Marantz 2226 I use in a small bedroom system. I plan on building a pair of speakers with Fostex drivers for it, just to see if I can. I'm fairly certain I can do this. I'm also a bit curious about tube amps. I've never had one, so I might give it a try. My Marantz has pre-out/main-in connections so I was wondering if I can use it as a pre to "play around" with a tube amp. I believe I can, but what amp? I don't want to spend much to experiment. $500 or less (preferably less) is what I'm gunning for. I saw a pair of Antique Sound Lab mono's on an auction site for $300, buy it now price. Would these be good to start with?. Room is 12x14 mostly classic rock and alternative, but it would be background music anyway. I also have a Marantz cd5001 I'll be using as well. Any and all advice is appreciated as well as witty sarcasm.
I think vintage Marantz receivers make great preamps. I currently am using a Marantz 2252b as a preamp with a pair of Marantz MA-700 monoblocks powering a pair of Klipsch Quartet's. Sweet sound,"tube" like.