Can I retrofit new radio w/ Sirius to a 2008?

[analemma]

I'd like to put a Sirius receiver in my MY2008 128i. Rather than pay the ever-more-ridiculous price for a new retrofit receiver (which is backorder for quite a while at the moment, as well), would it be possible to purchase the appropriate radio (incorporating the Sirius capability) used in a current vehicle and install it, then purchase the Sirius installation coding? I could easily run an antenna extension from the trunk as the car has Sirius prewire, or simply install an aftermarket antenna in the centre or the dash at the foot of the windscreen.
If this is feasible, it seems that it would be a better solution, as I know the capabilities of the Sirius/XM network have probably changed since the original receiver unit was design for the 2008.
Comments?
Anyone wishing to sell me a receiver box is welcome to contact me!