I have used BAS for two complete MK IX interiors and am very satisfied. I sent both sets of seats to BAS to rebuild and install new covers. My 61 MK 9 has Reutter adjustable seats and they are a nightmare to redo, but came out beautifully. They were featured on the BAS website for several years, light beige with contrasting dark green piping.
I purchased a Bassett interior on Ebay for my 52 XK-120 FHC in crimson red to go with the silver body color. It was made for Bill Welch around 15 years ago but was sold separately from the car that it was originally intended for. The quality is superb and I highly recommend Bassett. Bassett is renowned for his interiors and his seat foams are comfortable to sit on, unlike some that feel like cement.