Pass labs XA-160.8 monos - or -  Mark Levinson 536 monos for Magico's

Since you use the Bricasti M1SE why not consider their M28 mono's? I've heard them and wish I could afford them, bettered some Pass Labs I've heard. 

Luxman M-900u monos. Perhaps the ultimate until one jumps off the cliff. and it still may be up in rarefied air. imo

Luxman's are out of my price range. I would be able to just get one M-900u for close in price to other mono's.

My Magico S5 MK II need more. I almost went with one then upgraded later but I know how I am and would not have been happy with one and after this purchase my audio funds will be kaput so want to get enough amp for what I can afford but yes these are the amps I would get if I could afford them. 

As far as the Bricasti's. They are out of my price range also but there is a used pair of out there but even those are a bit out of my range but I love Bricasti for all their digital but for amps I like the amp companies for amps. I don't want a Pass Labs or Mark Levinson DAC but the Luxman does make a pretty nice SACD player but when it comes to Bricasti I don't there is anything better. Not even DCS.. 

I heard the Bricasti M28s compared to McIntosh 601s, Jeff Rowland 725 mono-amps, and Absolare tube amps in the same system. The Absolare is in a different price category, but was my favorite amp . The M28s were my least favorite with a very dark sound and not musical to my ears. All amps were driving Raidho C3.1s.

@fsmithjack   I'm a Pass Labs fan but not having heard the MLs I cannot speak to that comparison.

However, if you are open to other amps, @rsf507  's recommendation to pair your M1 SE (M12)  with the M28s, is an excellent one.

I was very impressed with the M28s (by themselves).  Once they were fronted with a full on M12, those I was with for that initial audition gave the intra-brand pairing even higher marks. I believe albertportis is listing both components.

All the best with your search and final choices.