Can ‘them’ be used for ‘their’ in front of a noun?

I’m having a difficulty understanding “could they just have that for them unreachable pleasure” in the following sentence. If them means their, my questions will be solved. I’ll take it like this: if they could just have a piano for their unreachable pleasure. But I’m not familiar with such case. Am I misunderstanding something important? Or does the ‘them’ mean ‘their’?

Owning a piano is for some a symbol of status. That’s very sad, because there are many gifted people who would like to give anything, could they just have that for them unreachable pleasure, that is now just looking decorative and impressive in somebody’s interior. (People and Pianos by Marinus J. van Prattenburg: p9) [bold font is mine]

Just for your information, the writer is a Canadian and lives on the west coast. (though I don’t know whether it’s relevant.)

Solution 1:

The phrase "for them unreachable" is an adjectival phrase which describes "pleasure". It is to be parsed as "...could they just have that pleasure (which is unreachable for them)".

Solution 2:

The actual phrase would be "have that unreachable pleasure." Because the pleasure of owning a piano is not unreachable for everyone, however, the author wants to clarify that it's unreachable for them.

You would generally see such a phrase offset by commas or parentheses to avoid just such confusion: "...to have that, for them, unreachable pleasure..."