I am going to ask for LDN next time i see my doc. so i checked with a compounding pharmacy i have used before for something else before. They had never done LDN before, but saw no problem with crushing up a full dose tablet and dividing it into smaller doses and capsules for me (using the fast release filler Avicel).
The only problem she had was that she would have to charge me for the full pack of full dose Naltrexone, not only for the amount of Naltrexone she used to fill my script.
The pharmacy is based in Sydney:
Fresh Therapeutics Compounding Pharmacy
M102 Broadway Healthcare
Level 1, Broadway S/C, 1 Bay St.
Broadway, NSW 2007
(never visited the web site...)
I spoke to the chemist called Mai (Pronounced as May). If u are in another state, i would guess they could organise delivery to the dr, a chemist or somewhere.
As I said, i have used them before for other compounded medication, and they are a fairly physically large chemist with a large modern looking compounding lab, so they seem reputable.
best of luck