Aha, someone else based in this history-steeped town; treachery, bloodshed, murder; hey don't you just love the FA Cup?
Don't know of anyone successfully using the big zoom Panasonics for digiscoping though this 2" William Optics eyepiece claims compatibility with FZ-1 (presumably on basis of exceptionally long eye relief) :
http://www.william-optics.com/accessory/dcl52.htm
Various teleconvertors have been tried successfully maxing out, as far as I know, with Jimmie Burton's stacked TCON 17 and TCON 14 on his FZ10 to give about a 1000mm equivalent (probably need to copy and paste this link) :
http://www.fototime.com/ftweb/bin/ft.dll/detailfs?userid={2EF17651-2565-41C9-8CA7-302B3086CB4E}&ndx=26&slideshow=0&AlbumId={11EF64F6-36E5-4BE0-B9F1-374122DE2039}&GroupId=&screenheight=600
A bit of vignetting there.
As you are aware this is not a digiscoping forum. We only allow IanF to contribute here because he is a super moderator with super-human powers (he does however go weak-kneed at the mention of the word fluorite; oops, sorry Ian).
As far as I'm aware, you're right that less ambitious lens designs than those in these Panasonics seem to work better for digiscoping. In addition to the swivel body Nikons and 4300, on BirdForum have seen the Sony V1, Olympus 5060 and others recommended. Thought this site was quite a good advert for Pentax Optios :
http://hem.passagen.se/gorbatul/
I am sorry I can't help re. a local digiscoping forum. Maybe Dave Smith who is a BirdForum member, a digiscoper (and based in Maldon) might have some contacts. His web site has his email address :
http://www.graviton.demon.co.uk/
A very warm welcome to BirdForum :t: