I can think of four very good options that I think will give you great performance:
Bryston. It is a brilliant match with Maggies and for a long time has been at the top of everyones list to pair with these speakers. It is definitely worth considering. Not sure bets Model
Chord Ultima 6 - This amp is going to be tonally similar to Bryston but with monster power reserved and runs cool. I think it is Class G or H as it has switching rails. List is a little high at $9.2K but is worth stretching for. The eTude at $5.8K has less power using the same tech.
Hegel H20 - A bit warmer than the Chord or Bryston but as clean and clear as them. This lists for $6K
These three will all deliver a big, clear and engaging sound. but it will lose a touch of the tubiness that you get with your Primaluna.
The AVM MA30.3 monos (half width units) use MOSFETs in th output stage and have a softer sound to them than the other amps listed here. There list for $5.3K.
I am a dealer for Chord, Hegel and AVM. I have no relationship with Bryston. I do have this exact model of AVM availabe for demo in-home.