From what I understand -
Cured LR is only truly cured and able to be placed directly in your existing tank only if it has came directly out of another existing healthy system, such as rock from your LFS.
You see the terms cured, precured, and uncured at alot of the online sites, in my opinion any rock that would be shipped to you would need to go through a curing process regardless. This is because the rock would have some die off during shipping, placing that rock into an existing tank would almost guarantee a cycle, and dead fish.
If I were in your situation I would consider two options
option A - Buy a few pieces of rock (depending on weight) every few weeks from your LFS, placing it directly into the tank.
obtion B - buy a box of "cured" "precured" or "uncured" from an online vendor, set up a tub
are tub or other tank with a skimmer, heater, and powerhead, place the rock in there with no lights, testing water every other day to watch for spike, do water change, repeat process for about two weeks until your water levels are good
The nice thing about buying uncured rock is that its a little cheaper, you will get a larger variety of hitchhikers(good and bad), but you do have the time and expense factor of the actual curing process.
Just my two cents
