Hi,
I can say that the Duberley relatives/ancestors I have looked at all link to Ruardean. I haven't been able to work out where the name first came to there from. Unless you are from a noble family, records are virtually non-existent pre about 1650ish in the area I was interested in. If I was forced to guess, I'd put my money on the name originally being French.

There are other Duberleys out there. The nearest geographically live in the Ross area, and there was a family in Monmouth, some of whom made clocks. A Lady Fanny Duberley wrote a famous book, but I'd say her husband was no relation to the Duberleys I looked at.

All the best

Nick