Would make any modifications to Paleo diet if no grass-fed meat, no wild-caught fish, no organic veggies and no pastured chicken/eggs were available? I understand that principles are the same but would you keep 100% the same or try to make some adjustments?
I probably wouldn't make that many adjustments, to be honest. I'd eat beef, vegetables, tubers and fruit, omega 3 eggs, and maybe some canned sardines. I would try to minimize the conventional pork and poultry fat, because of O6 concerns. I would also avoid conventional dairy. Other than that though, I'd just try to avoid your neolithic agents because I think that's even more important than eating grassfed, wild caught,etc. all the time.
I'd probably pop some fish oil, and ditto on Ashley Roze's thoughts on produce. I love strawberries for example, but I have a hard time finding reasonably priced organic ones, so I usually end up getting conventional ones and letting them sit in a bowl of filtered water for half an hr.
Ideal is relative - try to supplement with fish oil - I generally get organic veggies - not too expensive at farmers market - wild fish (canned or at fish store) if not too expensive - always organic eggs (I'll pay the extra buck)- on disability I live on $50 a month on food - sometimes don't quite make it - but chicken livers are all "organic" and cheap - $2 and I get 2 meals from a carton - I've had great results!