There are many other choices. I would select an amp that would mate well with your future Maggie 1.7s. I'm pretty sure that their are threads on this topic, if not, I'd ask that question and you'll probably get a better response.
One thing to keep in mind is that your Primaluna preamp has a rather high output impedance.
Here's an excerpt from Stereophile's review of the PrimaLuna, "The output impedance was also to specification in the midrange and treble at 2.7k ohms, which is higher than usual, but rose to a high figure of 11.5k ohms at 20Hz. This preamplifier really does need to be used with an amplifier having an input of 50k ohms or more if the bass is not to sound lightweight. At 77k ohms, the Prologue Seven's input impedance will be sufficiently high, I feel."
Your amp should have an input impedance of 10x the output impedance of your preamp so, strictly speaking, you would want an amp with a 100 kOhm input impedance, there are a number of those around, but you should be alright with a 47 kOhm input impedance as you will probably not be playing a lot of music with much 20 Hz musical content.
One thing to keep in mind is that your Primaluna preamp has a rather high output impedance.
Here's an excerpt from Stereophile's review of the PrimaLuna, "The output impedance was also to specification in the midrange and treble at 2.7k ohms, which is higher than usual, but rose to a high figure of 11.5k ohms at 20Hz. This preamplifier really does need to be used with an amplifier having an input of 50k ohms or more if the bass is not to sound lightweight. At 77k ohms, the Prologue Seven's input impedance will be sufficiently high, I feel."
Your amp should have an input impedance of 10x the output impedance of your preamp so, strictly speaking, you would want an amp with a 100 kOhm input impedance, there are a number of those around, but you should be alright with a 47 kOhm input impedance as you will probably not be playing a lot of music with much 20 Hz musical content.