Buy an Air Tight ATC-2 Line Stage and you will have a matched set (preamplifiers made for one another). I own an Air Tight ATM-2 Tube Powered Amplifier (85 Watts Per Channel), an ATC-2 Line Stage Preamplifier, and an ATE-2 Phono Stage Preamplifier, augmented with an ATH-1 Step-Up Transformer, both for my Basis 2001 Turntable with a Bob Graham 2.2 tone arm and a Koetsu Urishi Vermillion Cartridge. I also own a pair of Sonus Faber Electa Amator II, two way speakers, supplemented with an REL Studio II Subwoofer (194 pounds and dials into both left and right channels seamlessly).
Since the "old" (better in my opinion) REL subwoofers are hard to find, you might want to look at three way (full size) speakers, like a used pair of Sonus Faber Cremonas (NOT the Cremona-M (M for Monitor, or two way speakers) and then supplement them with two REL Stentor Subwoofers. Or you can go with the two way speaker option and buy the largest REL Subwoofer you can find.
Air Tight Preamplifiers (ATC-2, ATE-2) and my ATM-2 Power Amplifier combine to produce a warm yet amazingly accurate sound. You have one of the world's best phono stages or preamplifiers already, and I'm assuming it's MM or Moving Magnet, which means, if you have a high end needle and cartridge, you'd need to get either an Air Tight ATH-1 or ATH-2 Step-Up Transformer in the event you do not already own one (I prefer the ATH-1, even though it's an older model).
If you build your system around other Air Tight components, you can be assured of owning a truly world class stereo system, and with the economy the way it is, right now is the perfect time for acquiring quality used Air Tight equipment as well as Sonus Faber Speakers (it's a buyer's market). Now, most Sonus Faber speaker models work really well with Air Tight equipment, and whether you decide to go with two way or three way speakers will depend to a great deal on your taste in sound (enriched, warn detail or raw, loud sound).
Obviously, the more power you can get, the better, yet I've found that my ATM-2 is perfectly capable of running a pair of Sonus Faber Amatis (their top of the line 3-way speakers) as well as all of their two way, or monitor speakers, but with two way speakers, you're really going to need subwoofer support.
And if you can find a REL Studio II or Studio III, you can take advantage of what the two way Sonus Faber speaker design offers (and in my opinion, the best of these are the Electa Amator IIs): much more detail, beautiful mid-range (augmented, believe it or not, by the REL Studio II or III). And two way speakers don't experience frequency response conflict or cancellation from very high to very low signals within the same cabinets. I have two audiophile friends who own a pair of the Sonus Faber, top of the line, three-way Homage Amati Speakers ($22,000 a pair) along with expensive CAT mono blocks and preamplifiers, and they both like my line stage, phono stage, power amp, speaker and subwoofer combination system (which used, cost me less than fifteen grand) better than their own, $75,000 counterparts.
Anyway, and especially if you're just starting out, this is a direction to which I would give serious consideration. Happy hunting!