wrote

Dude, I'm pretty sure the Jet Commander was a production aircraft
(early 60's?) that IAI ended up purchasing and building on their own.
Am also thinking the original Jet Commander came with J85/CJ610's.
Been years since I've walked by one on the ramp.

Have no idea when they turned into Westwind's, but looking at the
link/picture you posted, that airplane looks like it might have
TFE731's on it to me. Don't know if that has any relevance to the
"Westwind" moniker or not.

From The Illustrated Encyclopedia of Commercial Aircraft, Bill Gunston.

ISRAEL Aircraft Industries' Westwind business jet may be traced back to
the American Aero Commander Model 1121 Jet Commander which was designed
by Ted Smith and first flew in January 1963. When Aero Commander merged
with North American Rockwell they were obliged to sell off the Jet
Commander to avoid conflict with US antitrust laws (the parent company
was already marketing the Sabreliner business jet).
Israel Aircraft Industries bought the entire jet Commander programme and
all production tooling and sales rights, and after refining the design
returned it to the market as the 1123 Commodore Jet, later renamed the
1123 Westwind.
The Westwind had a lengthened fuselage, more powerful engines and
tiptanks. The longer fuselage could accommodate up to ten passengers.
The first Israel-built Westwind 1123 flew on September 28, 1970 and 36
had been delivered when production ceased in mid 1976 in favour of the
Model 1124 which was re-engined with fuel-efficient Garrett-AiRcsearch
TFE73I turbofans in place of the pure turbojets used in all previous
models.
The first Model 1124 Westwind flew on July 21, 1975 since when production
of the aircraft, known as Westwind I, has been running at three to four
per month to meet heavy demand from United States business operators. The
pressurized cabin can accommodate up to ten passengers with a flight crew
of two. The interior arrangement can be altered to suit customer
requirements. The cabin is heated, ventilated and airconditioned. More
than 90 have been delivered.
A further civil version called Westwind II is currently under development
in Israel featuring drag-reducing Whitcomb winglets mounted atop the
aircraft's tiptanks, which are expected to improve cruise performance by
some 70km/h (43mph) and range by 560km (348 miles).

Bob Moore