A 1993 mini will have "dry" suspension, meaning it has rubber cones for
springs and conventional telescopic shock absorbers.

Hydroelastic or "wet" suspension is a quite different system which was
used for about 10 years between roughly 1964 and 1974.

The shocks have no bearing on the ride height of the car. The problem lies
with the rubber cones (dry suspension) and the knuckle joints. These are
what define the ride height. On 90's cars it is quite common for the cones
to collapse after about 40k miles. The knuckle joints also wear out lowering
the car.

HTH

If the wheels /tyres are the same type & diameter & on level ground it will
be impossible for one to be higher than the other, they probably mean your
suspension is lower on one side, check the distance between the top of the
tyre to the wheel arch, on both sides & work out yourself  how much its
dropped, your mini will be dry, the last wet mini was produced around 34
years ago, your shocks will not determine the height, the probable cause
will  be worn rubber cones and or worn knuckle joints, to remove & inspect
them you will need a cone spring compressor for the front ones, a good idea
would be to replace the suspension trumpets upon re assembly with the likes
of adjusta rides, then if you still have uneven suspension you can adjust it
to your own preference, if you are on a budget & just want a quick fix its
possible to put washers between the knuckle & the cone to raise the
suspension, or file off some metal off the end of the cone to lower the
suspension.

Steve68s.