As long as you don't really care, you can use a '68-72 single snorkel. In '70, the California vehicles used a '71-up style air cleaner. That underside has a hole in the bottom that will need to be plugged (from the outside, so that doesn't get sucked into the carb.).
Here is a relatively inexpensive single on eBay, just needs hole plugged.
https://www.ebay.com/itm/335029417532