Austin Mini A/C Problem and general assistance needed

Hi,

I have just got around to removing the air conditioning from my donor
1275cc A-Series MG Metro. It has the same engine as the Mini and the
air conditioning is a "Unipart" (Austin's accessory supplier)
aftermaket unit so it is quite universal. It is about 20 years old and
the guy I bought the car from said it needed regassing as it doesn't
chill.

I'll say straight away that I'm no expert in A/C but I very carefully
removed the system and have it ready for installation except for a fly
in the ointment.

On the dash there is a screw on control unit with 2 rotary controls,
one for fan blower speed, the other for temperature (you hear it click
when it turns through the position of the current ambient
temperature). My first problem occured when I unscrewed this and
lifted it slightly from the dash - at that point I heard a really
faint hiss (for about 2 seconds). When I lifted the unit further I
noticed it had a small diameter pipe (probably copper, around 1/8"
section) which was crushed at the point where it goes into the rotary
control - unfortunately it has subsequently severed. The other end of
the pipe goes into the main centre console ac fan unit with no unions
anywhere and is about 4 foot long.

When I unscrewed the main rubber plumbing pipes from the engine to the
interior ac fan unit, there was no hissing at all so I assume there
was no gas present.

If you're still with me, I have the following questions based on this:

- Is it possible to fix the controller (it really has severed flush
with the temp control unit with not much to play with)?

- Can I get a universal replacement which would join onto the end of
the pipe?

- Is this pipe's system continuous with the main refrigerant system -
ie if I re-gas the system, will it leak out from this point or is it
indepandant and just for temperature control

- Can the a/c operate without the temperature control if I solder up
the pipe (ie. just continuous output)

- In general, what's involved in regassing the system afterwards (and
does anyone know of a service centre that they would recommend around
SW London)

Any help in these areas (or general advice) would be most appreciated,

Cheers,
E.