If whole wheat PASTRY flour is available there, it may give you a lighter result than a 50/50 mix of whole wheat and white flours.

Also, if you don't have either kind of pudding mix available, an egg yolk or two might be a good replacement for it. The "magic" ingredient in pudding mix is a commercial emulsifier which isn't available to home bakers. Egg yolks contain a similar emulsifier, and they've been used for multiple generations in baking for that reason.

I'm not absolutely certain if either of these substitutions would be acceptable in that particular cinnabon recipe, because I've never made it or done the substitutions. But I hope the advice is helpful to you.