How much to spend on phono preamp

I would spend at least double on the phono stage. This is $1k cartridge with low output, you want quality phono that can bring out the best in it. Tonearm cable is very important too.

Excellent and fully adjustable choice would be the Gold Note PH-10.

http://www.tonepublications.com/analogaholic/the-gold-note-ph-10-phonostage/

@jackd How about the 
Musical Surroundings Nova II
http://www.musicalsurroundings.com/product/musical-surroundings-nova-ii/

Is it of similar quality as the Gold Note PH-10? 

I don't think it was as flexible plus it is discontinued. 

@jackd any suggestions for good preamp with a headphone amp under 1500$?

Are you trying to stay under or around $1500 for a headphone amp and a phono preamp?

@jackd yup

O.K. then I would suggest this combo.

https://www.lineartubeaudio.com/products/mz2mz2-s

http://www.vista-audio.com/products/phono-2/index.htm

Total should be just over $1600

JC3 Jr.

Agree with Jackd 1st suggestion GoldNote PH10 because of it's flexibility but mostly because of it's sonics.

Buy a herron. Last phono you will ever need. 

@jackd Does the GoldNote PH-10 support both MM/MC types? I could not confirm this online.

I can answer this, yes it accepts both MM & MC. I bought mine here.
http://www.audioasylumtrader.com/ca/listing/Phono-Preamp/Gold-Note/PH-10/-In-stock-and-price-lowered...

I am a fan (owner) of the PS Audio NuWave Phono Preamp. ( $999 )  The sound is exquisite and can easily handle MM/MC . Check out the specs at the PS Audio site.  I also like the ability of ripping ( DSD/PCM ) my vinyl direct to my computer/music server to preserve my collectible vinyl. 

as little as you can or as much as you have to!

+1 for anything Herron. I also suggest Lounge, Sutherland, or the JC3+

I bought a used Manley Chinook from a dealer and am very pleased with it. It is extremely flexible and you can roll tubes for a highly customized sound. I have used both MM and MC inputs. I have no desire to buy another. That does not mean that I won’t one day! LOL