Here's me singing an old Copper Brothers song with concertina accompaniment, recorded in 2008 when I was just starting to sing & arrange songs for concertina.
https://www.dropbox.com/scl/fi/6kntzlyowtli659zoalph/All-Jolly-Fellows-with-concertina.mp3?rlkey=ml9xjkaqgsev1g0cw834895w3&st=mkfx2geh&dl=0
I later added a chorus & changed the concertina part to split chords for simplicity. Here are the pdf, midi, mp3, music xml, and xml of the split chord version:
https://www.dropbox.com/scl/fo/wd1gi64va1e29ezjy7p8r/AEqsDTXFAg8g52QZGYb_tWc?rlkey=bk5tw8ygws0qwn4mpf28o6yqd&st=b4w9opzh&dl=0