Very interesting.
There have been all sorts of finds in the area - lots of flint, the site of a standing stone, the remains of a bowl barrow, Hut circles, loss IA enclosures.
Sod all about this stone though, which I guess indicates it may not have been there for very long. But who knows?
I wasn't convinced really. It's in a great spot with long views to the west and across to Caer Caradoc, but it's granite. Stones round here are mostly sandstone, with a bit of dolerite on the Clee and there are no granite outcrops anywhere near as far as I know. The concrete base means it's been (re-)erected and the lack of records for such a massive stone in an area of much agriculture - it's fairly remote bit not exactly deep wilderness - makes it seem more likely to be modern.