Please help ...integrated amp under $1200

As paraneer suggests, pick your speakers first. The MA Sliver 10 is a great speaker but I would want at least 100 strong watts to drive them properly. Not just for satisfying volume levels but for good control of the speaker so you can enjoy all they can do.

A good amp that you could get for close to $1200 would be the NAD C375BEE.

Decide on the speakers first and then find an amp to properly drive them.

Agree! If you do this you will be reducing your risk of wasting lots of money. Decide what type of speakers float your boat first (sealed box, ported box, panel, open baffle, horn, etc.), then select your favorite of these. Only then shop for an amp to match what your speakers require. Of course, you should also check out powered and active speakers as well, thus saving you the trouble of purchasing an amp.

Very happy with Hegel H80 which sells used for your stated price

Check this out!
http://www.rogueaudio.com/Products_sphinx.htm

I'd second the Croft. I recently purchased a Croft preamp & it really made my MA Silver 2 speakers sound so much more alive & musical. 50 watts at 4 ohms is probably enough for most people--it will easily get you over 100db. I believe one reviewer of the 10's even preferred them with his 25-50 watt amplifiers.