This is probably the best wheel to look for --> Honda 15" 4X100 ctr bore 56.1 used on CIVIC.
CIVIC, EX 89-on 4X100 56.1
CRX SI 86-91 4X100 56.1
DEL SOL, V-TECH 92-on 4X100 56.1
INSIGHT 01-on 4X100 56.1
PRELUDE SI 86-91 4X100 56.1
*Note all the Honda wheels I have ever had were ball seat*
I setup our Mini S with a spare tire from a late 90s VW Jetta (98 2.0 not VR6). I used the 15" wheel that has the larger overall dia. It only fits on the rear of the Mini. (I had the spare wheel sitting in the garage so I just used it)
The Jetta spare wheel is a 4X100 with a hub center of 57.1 v.s. the Mini's hub center of 56.1. That is only .5mm radius different. The other difference is that the Jetta spare has ball seats not cone seats. You can not get (14mm) M14 X 1.25 wheel bolts with a ball seat. I use ball seat adapter washers. The washers help center the wheel and I can use the Mini cone wheel bolts. I got some extra wheel bolts that have a gray finish just so we would have some in the event that one of the hex heads rounds off someday.
Wheel bolt info:
Mini gen2 2012 (R55/56/57/60 COOPER & S) wheel bolt: M14 X 1.25 (stock length 28mm) 17mm head with conical taper (check bolt specs for your year). Never use cone seat lugs or wheel bolts on ball seat wheels without adapter washers. Never use ball seat lugs or bolts on cone seat wheels.
Mounting the tire the easy way
I found a cover for the wheel and used a webbing strap to secure the spare wheel in the trunk. The webbing loops around the tire and the tails attach to the seat locking points. You should make sure the spare is secure and can not move in the event of a collision. The stock trunk net was used to make a pocket to keep our extra tools and our extra parts in the wheel's barrel. I extended the rear seats to the more forward position (rotate the strike pin 90 degrees). The trunk cover can still be used in this configuration. It is not very comfortable to sit in the back seat in this configuration but we can adjust it back if needed. (See step three photo below)
You may want to put wheel blocks/ chocks (Mini S does not have them) gloves, Ziplock bags, a few trash bags (to put the dirty flat tire/ wheel assembly in) and some hand towels in your kit.
I bet you know how to mount a spare tire but it just may help you if you think about all the steps as you collect the parts for your kit.
The steps to use the spare tire:
1) Make sure you use the parking brake when using the factory supplied jack. If you don't your car could fall of the jack. Wheel chocks would help.
2-4) Remove the trunk cover and place it in the car but make sure you don't fold the rear seat on it!!!

5) Remove the spare tire and all contents from the trunk.
6) Remove the jack from the lower compartment.
7) Set the jack to the needed extension to interface with the rear jack point. NEVER PUT ANY PART OF YOUR PERSON UNDER A CAR WHEN USING THE JACK.
8) Insert the jack into the rear jack point near the rear wheel you want to remove first. Even if the front is flat you need to remove the rear wheel first. When you are on the side of the road it is easy to start working on the front first only to find out you have to start all over.

9-10) Remove any wheel or lug covers. Remove the rear wheel by breaking the bolts with the wheel part way touching the ground (the E brake will help on the rear too).
10 continued-11) Jack the car up so the wheel is all the way off the ground (about 15mm). Then remove the rear wheel and place it under the car.
12) Place ball seat washers over cone seat wheel bolts when installing spare with ball seat holes.

13) Mount spare. Insert first lug by hand making sure it is snug.
14-16) Load the other lugs keeping the wheel centered and tighten lugs in X pattern.
Then you can swap the front if needed but move the jack to the front location. Repeat the steps that apply.
Print this out and put it in with the tools so you make sure you don't forget the details. It can be handy if a friend drives your Mini.