Packable and drain on savings account are relative terms but here are two options in different ends of the spectrum.
Feisol CT-3441S folded 17", fully extended 70", Weight 2.2 lbs, Carrying Capacity 22lbs, cost $300. Combine this with the Outdoormans Pan Head and your have a bomber set up that will handle the heaviest spotting scopes with a digiscoping rig.
Other end of spectrum Manfrotto 7301YB which comes with an ok 3way head. folded 20", max 56", weight 3.7 lbs, carrying capacity 7.7 lbs, cost $130. If your staying low to the ground it should be sturdy enough?
As always, you get what you pay for, the only set up I have found that is lighter than the Feisol is a Gitzo0531 but the Gitzo cost $100 more than the Feisol. For the extra $100 you save 8 ounces but you won't be as sturdy.
Hopes this helps, pm me if you want more info, I've got a decent amount of data on this topic.