I remade most of them on my 54. You just need replacement dyneema chafe protection sleeves and a fid set like this:

https://www.amazon.com/Samson-Selma-Splicing-Fids-Five/dp/B006L9GB48

Carefully open one up by removing the whipping threads. If you feel like it, replace the 4mm (perhaps it's 5mm) line inside. Mine looked fine, so I did not replace the internal line. Once you open it up, you will see how easy it is to make the loop. Restitch it as Amel's method of making the loop can possibly unravel if the loop is not kept under tension and vibrates a lot.

You will want to make an endless loop as per original and not use a soft shackle for this application, imo. First, you want the additional sun/chafe protection from the sleeve and also making a strong enough soft shackle that has that small of an inside diameter will be difficult. 

You could buy replacements from Amel but I suggest getting the fids and learning how to splice and also make soft shackles. In addition, you can slowly start replacing the hard shackles aboard with soft shackles. I bought some commercial soft shackles in the past and threw a few out because I realize how poorly the diamond knot was tied. Don't assume that buying it pre-made will mean that it's better.


--
Scott 
2007 A54 #69
SV Tengah
http://www.svtengah.com