Looking for a rub to use for a pig roast it doesn't matter either a commercial brand or a recipe.
Found this recipe for you.
Recipe for a rub, from Max Willmore
This is the basic recipe & you can add to it to increase amount needed. This is for aprox. 100 lb pig.
1 3/4 oz cracked black pepper
1 1/2 oz minced garlic
3/4 oz garlic chips
12 oz minced onion
2 large fine chopped onion
1/2 cup paprika
5 cups kosher salt
1/8 cup onion salt
6 cups olive oil
Mix all ingredients the day before & stir often. Lay out pig & rub generously inside & outside of pig. Any areas you can tuck in rub. Do it. Cook until deep parts of meat are 180 Deg.
I'd also like to throw the concept for a Mojo as a marinade into the mix. It's quite delicious if you're doing a Cuban style pig roast.
The site I've linked has a lot of information on doing a Cuban style pig roast, although I've linked directly to the mojo recipe.
Here is a link that might be useful: Mojo recipe for Pig Roast