Well, the cheapest Optolyth adapter I could find was $130 plus shipping which I thought was quite expensive for a small piece of aluminum. Knowing that both the tripod and the binos are treaded in standard Camera/optics 1/4" size treads, I improvised my own mount.
I used this adapter as the base:
https://www.bhphotovideo.com/c/product/1369420-REG/camvate_c0910_1_4_f_to_3_8_m.html
and this rod as the extension:
https://www.bhphotovideo.com/c/product/686707-REG/Matthews_350602_5_4_101mm_Rod_for.html
I quite like it because it brings the center of gravity higher and with the proper tension on the ballhead, it gives you a fluid range of movement with very little pressure required to move the binos in any direction.