Help me with a Fidelity Research FR64 part

Did anyone ever find a reliable source for this part? I have an FR-64s with the large base (B60). However, I would like to mount the arm on my Thorens TD-124. To allow the arm to fit the 124, I believe I will need to buy a smaller base. I see a base on eBay for the FR-64fx...not sure if it is what I need. Any suggestions would be much appreciated. All the best, Mark

Thanks Chakster! I received the nut and washer promptly, but did not get around to mounting it until this weekend, with help from my local dealer. Had to scrap off a bit from Swissonor’s arm board and the interior of the plinth, but was able to do so pretty cleanly and it does not show with the arm mounted. Got the exact pivot to spindle and arm height that we wanted. It sounds and looks great. Too bad the B60 base won’t fit. Actually, the washer didn’t fit either, but my dealer has some tools that could shave off part of the washer to make it fit. TD 124 has a low platter. Since this arm sits very low, I think it's a great match.