In both cases this an article:
And in both cases this article is the determiner of the noun »Güter« (goods, commodities, merchandise) which is genitive plural form of the neuter noun »das Gut«.
The nominal phrases, in which they live, are:
Subject of the sentence, in nominative case, plural:
die Preise der in Italien produzierten Güter
Dative object, also plural (dative case is not ruled by a verb but by the preposition »zu«):
den Preisen der in Deutschland produzierten Güter
Both parts of speech begin with the same core (but in different cases) which is »die Preise«, »den Preisen« (both of them consisting of a definite article, as determiner and a noun). Right of both cores are two very similar genitive attributes:
der in Italien produzierten Güter
der in Deutschland produzierten Güter
Both of them have their own core noun at the end which is the noun »Güter« and a determiner (here a definite article) at the beginning. Between the determiner and the noun is an attribute that again has its own attribute.
The core of this attribute is the word »produzierten« which is a participle (participle II of the verb »produzieren« = to produce) that behaves like an adjective (participles are verb-adjective-hybrids).
And in both cases this word »produzierten« (which, as just said, is by itself an attribute of a noun) has its own attribute which is an adverbial term (»adverbiale Bestimmung«) that consists of a preposition (»in«) and the name of a location (here the name of a country). Such local adverbial term satisfy the function of a locative case in other languages, so you might call it also a "locative term".
»in Italien« is an adverbial term and this adverbial term is the attribute of »produzierten«.
»in Italien produzierten« is the composite attribute of the noun »Güter«. The core of this composite attribute is a participle II which is by itself is attributed by an adverbial term.
»der in Italien produzierten Güter« is a nominal group in genitive case plural. It consists of a determiner (the article »der«) and the noun »Güter« which is the core of the nominal group. This core noun has on its left side an attribute (»in Italien produzierten«) which is a composite attribute
»die Preise der in Italien produzierten Güter« is a nominal group in nominative case. It consists of a determiner (the article »die«), the noun »Preise«, which is the core of the nominal group, and on its right side a genitive attribute (»der in Italien produzierten Güter«).
»den Preisen der in Deutschland produzierten Güter« is very similar to the item above, it just is in dative case, and contains another noun (»Deutschland«) inside the adverbial term.