I think it would be exactly the same. This whole sentence and answers needs reviewing - the translation I was given "He is going to make an x-ray" is in no way equivalent to the translation at the top here "He is going to get an x-ray". From an English perspective the first implies (in poor English) that he is a radiographer and the second that he is a patient!!
For reference, http://www.wordreference.com/enfr/x-ray indicates that 'la radio' is a common short form of 'la radiographie', which means 'an x-ray' (i.e. a photograph created using x-radiation).
According to the same page, 'faire une radio' means 'to x-ray' or 'to take an x-ray' (as in 'The radiographer is taking an x-ray'). 'To have an x-ray' (as in 'The patient is having an x-ray') is 'passer une radio'.
I tried various options in Google Translate. All three of: He is going to have an x-ray. He is going to make an x-ray. He is going to take an x-ray. translate identically to: Il va faire une radiographie. The latter translates back to: He will do an x-ray.
He will make a radio. translates to: Il fera une radio.
Il va faire une radio.
He's going to do a radio.
which seems pretty awkward to me as an English speaker. Finally: He is going to make a radio. translates to: Il va faire une radio.
So I presume radio can be an abbreviation for radiographie as mentioned by taramitzy but it could also be a radio. We need a native French speaker to tell us which of the various French sentences above are or are not awkward.
There are many commonly used abbreviations in French - think of apéro, aprèm, beauf, hebdo! etc. Duo has already used photo as an abbreviation for photographie in these exercises, so it seems reasonable to accept the similar abbreviation of radio for radiographie. The verb "faire" feels odd here, as it did when we first encountered "faire un rève", for instance. In English we would use the verb "to have" in both of these cases. But French is not English and we can't cram it into the same set of rules! ;-]
The expression "faire une radio" is not colloquial usage. It is an expression that will be understood by a francophone as either "take" or "get" an x-ray. It means that someone is going to perform the x-ray. Literal translations will often take you away from the actual meaning. We need to recognize the expression as a single Translation Unit--not a word-for-word translation.
The expression "faire une radio" means "to take an x-ray" but may also extend to the idea of "get an x-ray". For example, a doctor may say "nous devons faire une radio de votre cour" = we have to take/get an x-ray of your neck. If you "have an x-ray", it means it is being performed on you.
I can see that this is idiomatic in French but a variety of translation engines, including the reliable Reverso, give the same French for 'he is going to make a radio' - so Duo should accept it.