Hello John & MG:
My ancestors are from the same area and I have Harasims in my tree, too. I also have "Cymer"...maybe/could be "Cuper"? I couldn't help but notice that Harasim is a bit common in the area, so I don't know if my Harasims are your Harasims, but I would like to share my info. All of my Harasims are by marriage and the earliest is Marcin Harasim (married to Agata Kopiecz) born (totally guessing) around 1760. They had 3 children (that I found so far)...Jan, 1798...Adam, 1814...Marianna, 1819.
The Harasims and Cymers married into my Obiedzinskis (Augustow area, possibly Topilowko) and Gudanows (Zarnowo). I am desperately trying to find Obiedzinski and Gudanow info.
The priest in Rajgrod has probably 75 old books from all over the area. I found many Obiedzinskis, just not my specific one. I went to the Suwalki archives, but did not spend enough time there! The Barglow priest has only Cyrillic books from the late 1800s. I do recall seeing a Harasim in the Barglow cemetary. He said that all of his books are in Lomza.
The areas I am currently searching are around Netta II (formerly Borsuki before the Nazis burned it down), Augustow, Sosnowo, Barglow K. and Zarnowo. I do recall seeing Kotarski, but never wrote anything down about it.
Thank you for allowing me to share!