Dan Sullivan made plenty of 78 rpms, I am not completely sure about re-issues, they do come up on compilations of old recordings. Their version of The Blackbird, with piano introduction by Sullivan, before the band joins in, is a must hear, for a number of reasons.

Tom Morrison didn't record all that extensively, his few sides of 78 rpms do tend to appear on those old compilations. (Not much use to you there, in my time kind people supplied me with endless tapes of dubbed 78s so the re-issues passed me by a bit).

If you're into that sort of things though, the extensive re-issues of John McKenna's flute 78s are a must hear/have, especially the most recent collection from the John McKenna people in Leitrim.

Felix Doran had his own lp, 'Last of the Traveling pipers' but other bits and bobs appeared here and there.