As a tripod head, I use a Gitzo GH1720QR for my 65mm scope. I really like the single-knob locking system (for both pan and tilt) and it is lightweight and fluid enough for me. It has no counterweight system however. I don’t find it a real issue, except for digiscoping.
If you want to digiscope with anything heavier than a smartphone, I don’t think it would be satisfactory. (I’ve tried it with a DCB-II adapter and it was totally out of balance, which isn’t that surprising for a 65mm scope, no counterweight and no offset placement using a longer tripod plate. My latest trials with a small action camera directly connected with a custom adapter ring, weighing even less than my smartphone -see another forum tread-, seem to show it to be fine.) I’m considering a tripod head with counterweight, like the GHF2W, but it is heavier and expensive. However, taking an adapter like a DCB-II with a regular camera etc. would be contradictory to the quest for a lightweight setup and probably also require a heavier tripod :-D
For the tripod itself, I guess you’ll have to go to carbon as one of the ways to save weight. Is it mainly weight you want to save, or also size when folded? That might influence choosing 4 section-legs (more compact folded) or 3 legs (more stable) (considering same materials, max.height etc.).
There are many brands: Gitzo, Manfrotto, Sirui, Velbon... with many models, in different price classes.
I’m really no expert in this, thus I will let others give their advice or recommend searching for similar threads in this forum or rather the tripod forum. I think there are already a few general threads about tripod(heads) for 60-65mm scopes.