The OS Benchmark database lists 6971 bechmarks with "FARM" in the description. Not all benchmarks are in the database, and this list does not include FB (Flush Bracket - metal plates).

Too many to look at but: TRENOWETH FARM, BRANE FARM, VENTON VISION FARM, PAULS GREEN FARM, HALGARRACK FARM, CARVOLTH FARM, KYNANCE FARM, TRELILL FARM, CARNARTHEN FARM, PEMBOA FARM, GWEEK FARM, ARDENTALLAN FARM, TRELISPEN FARM

all in the OS squares SW (not a cardinal direction) & SX eg Cornawall area.

I may process all 6971 and put on my website as TXT file. If anyone wants to find a weird name. I will capitalise them properly. Post request & check back later.