I need a good Preamp

My current system:
Preamp:           MAC C2300
Amps:              Krell FPB 350mcx mono blocks
Speakers:        B+W 801 Series II

My MAC C2300 just quit working and really I need it in another room to pair with a MAC MC452 once it gets repaired. So, I need suggestions on what will mate up well with my Krells? I would like to spend $8k or less but I would consider going higher. I am thinking a line stage even though I did use the phono on the MAC some. I plan to add a phono amp to my system later. I just play cds with this system. Reading on this forum I sort of lean towards a used ARC 5SE or maybe a Cary SLP05 but I am open to suggestions. There are no audio shops close to me so I will be buying without getting to demo anything. I'm not too knowledgeable on stereo gear so I need some help. Thanks for the responses.
Check out the PS Audio BHK preamp. It's well under your budget, sounds great, tube rollers delight and will mate with any amp. 
wemfan, FPB300 and FPB600 are cut from the same cloth. I prefer the FPB600, felt it had more control, like driving a V8 vs V4.  Even around town at low speeds, you always feel the V8 torque and power.   

I'm familiar with FPB650 mono so my guess your 350mcx is similar to the FPB600 with better separation.

Before FPBs, I had a Krell KSA100s and it was very very dark in comparison.

At the time, Krell was my favorite SS amp.  Great bass, neutral, dynamic but bright and hard and always use MIT cables to tame it. The ONLY reason I sold FPB600 is try something new.   It's one of my all time favorite amp with great great memories.

VAC preamp is a great match.  It has low impedance so can drive anything.  Very sensitive to tube rolling so you can tailor sound to your taste.

I've heard good things on PS Audio BHK preamp so worth checking out.
I too have a McIntosh MC452 and had a McIntosh C50 (solid state) preamp, which I replaced with a C2500 (tube) unit, sounded a little sweeter than the C50...but then swapped out the stock tubes for a set of Genalex Gold Lions, once broken in, just sound so "musical".  The C2500 is a "keeper".  As this has recently been replaced with a C2600, you might pick up a good deal on one of the remaining C2500's.
Vac or an ARC Ref 5 se. Different voicing, so this is a personal choice

You first have to realize that spending more money on anything audio will not give you, "your better sound." You can spend a ton of money on two different automobiles sight-unseen, for example, and while both would demand quality and performance doesn't mean that they are both equal. You can end up with a Rolls Royce or maybe a Lamborghini, so did you get the drive that's right for you?

Combining apples and oranges may not be completely satisfying, like dropping the Rolls Royce engine into the Lamborghini.

l second mechans question to you, about what kind of sound you're hoping to achieve? If you're not sure, spend a couple of days at an Audio show. These, pop up all over the country.

IMO - Don't spend thousands of dollars until you have figured out what you like to drive.