Inexpensive amp for a McIntosh C46 Preamp

You don't mention what your budget would be for the
amp. I would try to find a good used Mc Amp here on AG. I have a MX135 and 2 Mc amps and think they belong together. What speakers will you be driving? I see MC162s listed all the time here on AG. One thing to keep in mind, a used Mc amp you settled for today will always return a larger portion of the purchase price upon resale than most any other amps.
Jaybo is right the 6900 is a great piece but so is the C46
, I think the C46 would offer a better foundation to build upon in the future.
Just my opinion of course.

Another amp you may consider is Sherbourn, that company was started by some ex-McIntosh guys. That is a very good amp for the dough.