*No sarcasm intended*
These switches are almost "a dime a dozen" and can be found on most 1st gen (R50,52,53) at any local salvage yard (if you have one near you).
After I broke one of the metal tangs/clips off my TPMS while removing my ebrake console - The salvage yard charged me $2 for one.
.AllMag (FL), has one for $21

 

Unfortunately I live out in the middle of nowhere and there are no convenient salvage yards nearby. So, first place I went to was Mini Mania's site since they are only a couple hours from me I usually check there first. $157.99 for the switch: https://www.minimania.com/part/NMI86...ch-R50-R52-R53 so then I posted here.
Though, I finally ended up figuring out just the right keyword to use to find the same switch on Way Motorworks site and bought it there for $27 or something like that.

 

Ah!
On an outside chance: I kind of figured you might not have a salvage yard within your locale.
I knew of an '05 R52 at salvage yard not far from me so I headed out this morning and pulled the TPMS for you.




Glad to hear you were able to source one from one of our trusted vendors.

 

Thanks man! If there is anything you need LMK. A few things I have for a supercharged engine are a throttle body, bpv, oem crank pully, belt tensioner.

 

Awesome!
Back at you - thanks!
Please don't hesitate to PM if you ever need any good condition salvage yard pulls/parts.
I'd be more than happy to help you where I can.