I haven't ordered from them, but they do have a minimum, think it may be 10. Only company I know of that will sell one set of reeds is Harmonikas in Czech republic, haven't tried their hand mades yet. Junior Martin(actually Penny) sells them for a mere $400 a set, and I think Jesse Brown (Choupique Accordions) will sell some cheaper.
I don't think you can get reeds in high A, the highest I've heard of is F. I'm guessing what you are referring to relates to lower quality reeds and construction. I'm assuming the Regal's reed blocks are all standing, which loses some sound in itself, but I would think that would be more noticeable in the lower keys.
Reed blocks all standing. I considered gluing them down, but you said it would probably need to be retuned then, and I just didn't want to sink more money into the box.
My observation is that the C and D boxes sound the best.
A boxes can sound murky.
Reed quality and the block construction are the two main factors here followed by tuning.
A very famous Quebec accordeoniste.. Alfred Montmarquette, born Montreal 1970.. died 1944..
Was a highly skilled, self taught one row player. It is my understanding he played exclusively on "A" boxes.
I have Smithsonian Folkways Records 00111 cassette tape of Montmarquette.. fantastic stuff.
I also have a CD by one of my favorite Quebec players, Gaston Nolet.. who put this out a couple years back.. all one row in A dedicted to Montmarquette. Several other excellent Quebec musicians are also on this recording.
I have posted a link to Montmarquette on youtube.
I have two Hohners in A... HA112, HA113
I would like a box in A specifically for Montmarquette style. Thou8gh could be played on other keyed boxes.
I believe Montmarquettes boxes were three reed.. I'll get some details and post them later.
Gaston Nolet played a Quebec made MELODIE "A" on his Montmarquette tribute CD,
it was also MMH no low reed.
Of course it would be possible to play the music on an LMMH in "A" and a vast improvement in getting rid of the muddiness by closing the L stop.
Modern Quebec accordeonistes play Montmarquette tunes on D boxes..often with all four of the LMMH reeds.