Wow - I may come looking for your lovely butcher. You're not that far from me!!
Presumably the bone density and composition is similar to chicken - might be worth checking on BritBarf - so I can't see any problems. I'd just portion them out into reasonable amounts and stick the spare in the freezer.
Mine love necks and have eaten most of the components, just not in carcass form, with no problems. I'd draw the line at heads just cos it makes me feel squeamish but my dogs probably wouldn't

I seem to recall that poultry carcasses are app 65% bone - another Britbarf nugget of info. Although it sounds as if you might have more meat than usual, particularly if you still have the organ meat. Lucky you
Kindness is the language which the deaf can hear and the blind can see ~Mark Twain