In 1978-80 on a few trips to Tel Aviv I visited a little "junk shop" in the stretch of Allenby Street that leads to the beach.
It was run by an ex- Zion Mule Corps man & amongst his wares were military insignia of that time & also some earlier bits & pieces.
I bought myself lots of insignia & berets & I got more for "Surplus Supplies of Cambridge which I passed on to them at cost price.
At that time you could buy headgear & rank insignia but I was unable to buy cloth formation signs, being told it wasn't allowed.
In Ben Yehudah there were a few surplus shops where you could find old respirators, dust goggles & the like.
All those places will be long gone, but try contacting Alex at "Historiama", he sells militaria & perhaps he can steer you to other outlets:
http://www.historama.com/history-sho...militaria.html
Some Israel based sellers offer items like insignia & berets on eBay, try contacting them in the hope they have suitable stuff that you can pick up?