I don't know if anyone has tried this yet:
I did a google search on Jasco Lemon Oil and Jasco has a website here is the link:
http://www.jasco-help.com/cgi/store_locator.pl?code=4301-4&state=all I've looked at number of stores by me, they do not have it......I did find Old English, Halloway House and Formby's Lemon Oils, but was hesitant to try any of them, as NONE of them list any ingredients.
Ace Hardware was listed on Jasco's website, they had two Jasco products but no lemon oil and they looked it up on their computer for me and said it they don't stock it.
I have not checked all the info on the Jasco site tho.
The funny thing is many years ago before I owned an Alembic or really knew anything about them, my parents had a bottle of Jasco lemon oil in the house and I tried it on the fretboards while cleaning my basses and it worked really well.
If Alembic still uses it, you have to be able to find it somewhere.
if I get more info, I'll let ya'll know
B.