For the linetype-based approach:

Copy and Paste the ARC150 Shape definition from my 4th post into a plain-text editor such as Notepad, and Save it to a file with a .SHP filetype ending [call it whatever you want].  I think you need to make sure the file does not end at the end of the code content, but on an empty line below that [Enter to get that if needed -- depends on how you Copied the definition from here].  In AutoCAD, use the COMPILE command on it, to make a file with the same name but a .SHX filetype ending.

Copy and Paste the Linetype definition (in my 1st post) into a plain-text editor and Save it to a file with a .LIN filetype ending.  Change the red part to the name of your compiled Shape file.  I think likewise the file needs to end with an empty line.  In AutoCAD, use the LINETYPE command's Load option, and the File button to get to your file, to load the linetype.  Apply it to things just as you would AutoCAD's standard linetypes.

Note that at an effective linetype scale of 1, each bulge of the S-waving is 2 drawing units wide [the height is a little less than the 1 unit in the ARC180 definition].  You will need to apply a linetype scale to get them the size you want.  In use as a Leader, the Dimension Style and Dimension Scale determine the size of the arrowhead, but the S-wave size is independent of the arrowhead size -- you can control them separately.

It's easier if you put both files into some location where AutoCAD knows to look [see the Support File Search Path list in the Files tab in the OPTIONS dialog box].

[If you really need tangent line bits between the ends of the arcs, that can be done with a slightly longer Shape definition.]