How to pronounce the family name "Penhallow"

How to pronounce the family name Penhallow? I'm translating the story "A Tangled Web" by L. M. Montgomery into Russian.

I would pronounce that /penˈhæloʊ/ but there might be a particular Cornish way of pronouncing it — Penhallow is a place in Cornwall — or a Canadian way. I can imagine that Cornishmen might say /ˈpeloʊ/ or /ˈpenloʊ/.

Being a Penhallow the name is pronounced as follows, disregarding local accents. Pen ( like something you write with) ha ( A like that in bat, cat etc) llow ( like grow, toe etc) the emphasis is very subtly on the ha. in Russian it is translated as пенхаллоу ( this is my name in the credits of a Russian to show I worked on)

Perhaps that's a common enough name in Canada, but here in the US there would be no canonical way to pronounce "Penhallow", so you'd have to ask the holder of the name.

There is perhaps a certain small subset of names that have an expected "correct" pronunciation, (eg: Smith, Brown, etc), but this is not in them.

Complicating matters is that it contains the word "hallow", which different English accents pronounce differently. I doubt it is consistent across all of Canada. For instance, where I live that word is pronounced with a short a and the "ow" as a long o for the sense of "to make holy", but more like a short o and the "ow" as either a short a or more like an "er" if it is in the sense of "a valley between two hills".

Your best bet is probably to either change the question to "Canadians: If you were saddled with this last name, how would you chose to pronounce it?", or to just pick a pronunciation you like, and move on.