How far & long do you need to travel? Also, do you have power at the hunting site?
If you have power at the hunting site and will only be traveling 5-6hr, just pull a small utility trailer and stick a cheap chest freezer in it. Set it good and cold before departing in the morning and if left closed, it should stay frozen until you can get to your destination and plug it back in.
Other option is a big cooler with dry ice.
Tammy & Mike
Ford F250 V10
2021 Gray Wolf
Gemini Catamaran 34'
Full Time spliting time between boat and RV