You can use regular oranges and lime juice instead of the sour orange. I don't remember the ratio though, maybe Craig will.
Sometimes we do a paste of garlic, salt, cumin, oregano, and EVOO, and rub into meat that has had some holes poked into it, but not always. Always gets soaked in sour orange juice and thin sliced onions though regardless.
I usually use a mixture of mayo and yellow mustard, mostly mustard, but it's been so long since I had made them at home that I didn't remember the mayo until after the first batch of sammies was made and into the oven, so I didn't bother with the second batch, just used the mustard.
I want to make egg rolls using Cuban sandwich ingredients, with maybe a chimichurri dipping sauce.