No, there is no ambiguity.
(Купить нашу продукцию оптом) (и в розницу можно в специализированных магазинах.)
If you parse the sentence this way, then the first part of the sentence is meaningless. "Купить нашу продукцию оптом" is not a full sentence and does not convey anything meaningful. So in this case, only your first option is correct.
However, if you phrase it as
Купить нашу продукцию можно оптом и в розницу в специализированных магазинах.
then indeed it becomes somewhat ambiguous. It can be theoretically interpreted as "wholesale and retail in special stores", as well as "wholesale from us and retail in special stores". However, even here the second meaning sounds really contrived. (I would say that the second meaning is still incorrect, but bordering on the edge of a mistake that a native speaker can make.) There are two reasons for this.
Firstly, the sentence does not have anything that would correspond to "from us". If we consider that "в розницу в специализированных магазинах" is separate, and "оптом" is separate, then it is not clear where one can buy products wholesale. It may be implied by context, but no such context is given.
Secondly, this meaning assumes some contrast between the two parts (оптом vs в розницу), so a more natural way would be at least to use a comma before "и" (still somewhat contrived):
Купить нашу продукцию можно оптом, и в розницу — в специализированных магазинах.
And it's even better to use "а" instead of "и" (absolutely natural, if context explains where you buy wholesale):
Купить нашу продукцию можно оптом, а в розницу — в специализированных магазинах.
Both cases would also require a dash (as shown), because the verb ("купить") is omitted in the second part.