Ofrece un sonido envolvente, una plataforma que se desliza bajo los pies y una pantalla de 32 pulgadas, todo eso "a un precio superior al de una cinta de correr doméstica sin pretensiones que podría suponerle unos 500 dólares"

"set you back " is an idiom for costing you an amount of money, often with the implication that the price in question is high or excessive;

"costarle unos 500 $"

https://www.collinsdictionary.com/dictionary/english-spanish...
3. (informal) (= cost) costar
the dinner set me back £40 la cena me costó 40 libras

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Note added at 1 hr (2023-07-19 10:41:53 GMT)
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https://www.collinsdictionary.com/dictionary/english/set-bac...
2. PHRASAL VERB
If something sets you back a certain amount of money, it costs you that much money.
[informal]
In 1981 dinner for two in New York would set you back £5. [V n P amount]

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Note added at 1 day 2 hrs (2023-07-20 11:57:00 GMT)
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Definitions of 'cost' and 'set back':

https://www.collinsdictionary.com/dictionary/english/cost
Synonyms: sell at, come to, set (someone) back [informal], be priced at

https://www.merriam-webster.com/dictionary/set back
2 : COST
a new suit will set you back $200

https://dictionary.cambridge.org/dictionary/english/set-back
set someone back (something)
phrasal verb with set verb
UK /set/ US /set/
present participle setting | past tense and past participle set
informal
Add to word list
to cost someone a large amount of money:
Buying that suit must have set you back.
It's a handy gadget and will only set you back about $15.

As you can see, this Cambridge Dictionary reference suggests that 'set back' can be used instead of 'cost' when the amount is a large amount.

The example sentence, 'Buying that suit must set you back', is a perfect example. Notice how, here, there is no complement, no amount specified.

However, in the second example sentence, 'It's a handy gadget and will only set you back about $15', I believe 'set back' could be replaced by 'cost' and this would not change the meaning of the sentence in any way.

If you compare your sentence with this second one, I am sure you will agree that, in yours, if you replaced 'set back' with 'cost' you would not be changing its meaning in any way either. As Collins suggests, it is just an informal way of saying 'cost'.