I own the non-revised edition of Agricola.
I want to get the FOTM expansion - but it looks like only the expansion for the revised edition is available.
Would this expansion work with the non-revised base set?
The simple answer is no the updated Farmers of the Moor is not directly compatible with an unrevised Agricola.
Mostly this is due to changed terminology and art between the classic and revised versions of Agricola.
The longer answer is that you can use the new expansion with the unrevised edition, but you will need to spend a little bit of time "patching" the rules to be compatible with the base game.
Helpfully Harry Bosch over on BGG has done most of the work for you: