if you want a LSD and not a full locker then tru-tracs are probably your best bet. they are a gear type LSD. no clutches to wear out or fluid additives to use. some companies use the tru-trac style as an oem LSD. you could find an oem LSD from the gear centre for less but it will wear out eventually and the additive will be needed. as well i am unsure if they would have something for the front diff if you want to do both.
or, ive used a lock-right (same idea as aussie) for years in the rear of my jeep when it was a DD. i got used to it and enjoy the way it handled winter and summer. i put one in my current DD because life without a locker is pointless.