TAG Heuer for the past few years have been running a recruitment drive for watch repairers and trainees. To that end, they are looking to complete more repairs in-house.
We no longer have a parts account with TAG Heuer so cannot obtain any case parts including the case middle section which is a shame because it was very popular and made for a viable repair for owners of these watches.
The only option is to find another authorised workshop or TAG Heuer themselves but unfortunately, at their prices.