I have made exact reproductions in aluminum of the underdash casings. They fit the later S1 3.8 and I think early 4.2 LHD cars.
They are copies of my original ones.
BD20464 Scuttle top casing, RH
BD20465 Scuttle top casing, LH, left of steering column
BD20471 Scuttle top casing, LH, right of steering column
SNG has them on offer, however they seem to be cut incorrectly.
The price is for a set: 15GBP or equivalent in EUR/USD paid to a paypal account.
They can be shipped by post for probably about 5-7GBP.
If anyone is interested, please contact me directly.
Tadek