Any suggestions for a metal workshop suppliers? (SW based but not sure it matters particularly)

Have a done a couple of sketches, if anyone has any ideas:

The centre part is based on the existing dilapidated structure that did have planning to be rebuilt (now lapsed) but I would like to add a car port section on the south side and an office on the right side, all subject to planning of course.

Centre section would be internally insulated, needs to be high enough for a 4×4 on a 2 post lift with enough height for me walk under it, car port must be high enough for a livestock trailer (2.5m access height min) and I the office will be well insulated and probably timber clad to soften the look.

Looking at double pitch as it breaks the building up to make it less dominating (we are just outside an AONB), am planning solar on the south facing roof (car port side) and roof lights on both sides. The car port will be double use with provision to set up lambing pens and some hay storage.

Pitches are not great but trying to maintain roof height for the lift and trailer access.