Front master cylinder sight window

The sight window on the front brake master-cylinder of a KZ750L3 I'm currently restoring is quite yellowish and I would like to replace it. On partzilla, I see that it was not available by itself but can it be replaced anyway? Any other source for this part? (OEM from another model or jobber)
I know I could replace the whole master cylinder but for now, I'm only looking for the sight window.
Thanks!

Did a google search and this was at the top...

Thanks Nessism! I'm not afraid by the procedure; I already replaced the engine oil sight glass on the clutch cover on one of my previous ZX-11. The unit was available from Kawasaki and it was held in place by the pressure of the built-in o-ring.
What I mainly am looking for in my KZ750 project is a source of the master-cylinder's glass itself as it is not listed on Partzilla or Kawasaki's online parts catalogs.

No eBay APP ID and/or Cert ID defined in Kunena configurationI replaced both clutch and brake sight glasses on my Magna eight years ago with these. They are real glass, not plastic. So should never yellow. I don,t know if they fit your bike.

This guy on ebay replaces them

Or you can do it yourself and buy the glass to size. I did my gpz1100 and its still fine after 3 years. I bought the sight glass kit from 'new river cycle salvage llc'

They advertise on ebay and if you can't see your bike listed you can contact them and they will make to size.

wrote:

This guy on ebay replaces them

Or you can do it yourself and buy the glass to size. I did my gpz1100 and its still fine after 3 years. I bought the sight glass kit from 'new river cycle salvage llc'

They advertise on ebay and if you can't see your bike listed you can contact them and they will make to size.

I just ordered glasses from "New River Cycle Salvage llc". They have the ~22 mm diameter glass I need for the KZ750.
Many thanks for the information!

Yamaha/Nissin sight glass pdf >>   www.xj4ever.com/choosing%20a%20sight%20glass.pdf
I have no idea if anything in this pdf would be useful for a vintage Kawasaki master cylinder. 
tags. mineral glass. glass button. site glass. plastic sight barrel.

Related. The 650-CSR & 750H Ltd master cylinder sight glass is encased in a metal ring & rubber seal (~25mm). Z1Ent sells a 25mm oil level gauge sight glass, but I have no idea if either the whole thing or just the glass & seal could be used w a master cylinder.