best class a amp for a grand?

That would be fine. You would need an F5 or J or J2 or M2 - I think the other ones would be under powered. I do think clone is the wrong word, they are Nelson Pass originals and further refinements upon the orignal Aleph 3 and 30, especially the J. There is a fella named Rawson that has produce a series of Pass/First Watt clones that can be had for less when they come up on Agon - they are likely to perform similarly.

You might find a Sumo Nine, they are getting old, but still a nice sounding amp... 60 to 8, 120 to 4

Pass Labs Aleph 30 or a Parasound.

Which parasound runs class A?

I think they are all A/AB.