You might want to hang onto that new F35, since it may be one of the last new ones with the LSD installed that readily available. A search on Dr. Google for a new F35 with LSD turns up only a couple sources that are several months old and those were listed at a whopping $3000+. A few hits show up for a non-LSD F35 at marginally less $$. There are plenty of rebuild F35s, also north of $3000, that can be purchased, but are also requiring a core return.
A search for new F23 transmissions comes up with a few more results on Dr. Google, but as you stated, no factory LSD. Only aftermarket LSDs are available for installation.
The search for F40s comes up with many more sources of new transmissions. The majority are sans LSDs, but a Saab 9-5 Aero 6 speed can be ordered from Europe with a factory LSD - but hard to locate and big $$. Cheaper to order a new F40 and LSD (a Quaife is really the only way to go) and install it yourself for about 1/2 the price of the Saab.