Recently one of the gate nuts in my V3 sump disappeared and I suspect it became loose, fell to the bottom of the sump and it was sucked up when my LFS cleaned the bottom. Red Sea sells the entire gate plus the nuts in a package but the rep at Red Sea that I contacted found me a small package that just contained the nuts and it cost only $8 plus $4.30 for shipping.
You should contact Red Sea directly and ask is they will sell you the feet alone and not have to spend $52 for a package that contains parts that you do not need.