Trem arm collar

I'm trying to fix up the floating trem on a Monark and it's missing the collar. I was just wondering what function the collar serves and whether it's possible to simply attach a trem arm?

nh

Well I just ordered a whole bunch of trem arms from Stewmac... Hopefully one will fit

Now for the locking nut!

Another question that most likely has an answer already:

Does anyone know if the shims that come with a Kahler string lock (https://www.kahlerusa.com/guitar-tremolo-and-bridge/5513-string-lock-standard) would fit in the string lock of a Monark?

I was also considering a "fudge" job where I would glue a washer to a nut - the washer acting as the shim. Without the glue the nut would just spin...

nh

Depending which trem you have. All can be fixed anyway.

http://www.westoneguitars.net/fixme/hardware-repairs/bendmaster-ft-tremolo-collar-insert-replacement/. 

Also google Kahler trem parts.
There's a site that stocks loads of bits. Plenty on Ebay too.