Plz can any one tell me the substitution of corn syrup?

I need to make marshmallow and walnut halwa, Im in Spain, tried but couldn’t found.



* 10  large corns without husk
* 1  250 gram salted butter
* 1tbl paprika
* 1 tps salt
* 2  garlic cloves


* Pre heat oven to 220

  Mix room tempture butter, shredded or crushed garlic,paprika in a small bowl. Cut corn in half. Rub enough mixture on each
  "cob" until covered throughly. Wrap each "cob" in aliminumn foil. Place in oven cook for 25 mintues.